When no `contentContainer` has been specified in Sidebar's config, avoid
setting it when calling the `BucketBar` constructor. This leaves the
responsibility of determining how to observe whole-document scrolling up
to the BucketBar.

During code review it was suggested that "content container" might be
confused to mean the content of the bucket bar.

In current usage of the `BucketBar` we only ever have a single scrollable
container to observe. Simplify the `BucketBar` API to pass in this element directly
rather than a selector and add associated tests.

Prop-types checks are now globally disabled because we're using JSDoc +
TS instead.

Bumps [elliptic](https://github.com/indutny/elliptic) from 6.5.3 to 6.5.4.
- [Release notes](https://github.com/indutny/elliptic/releases)
- [Commits](https://github.com/indutny/elliptic/compare/v6.5.3...v6.5.4)
Signed-off-by: dependabot[bot] <support@github.com>

Components no longer have a `propTypes` property.

We no longer set `propTypes` on components.

This enables checking by TypeScript

Prop-types checking has been replaced by JSDoc + TypeScript.

Prop-types checking has been replaced by static checking done by
TypeScript.

Detecting a Preact/React functional component that does not use `propTypes` is
impossible to do with 100% accuracy. `function Foo() { return 'Hello' }`
is a perfectly valid component with no obvious Preact/React features.

Fortunately because of the way this helper is used, we can make do with an imperfect
check. If `mockImportedComponents` mocks something which is not really a
component, that mock will be overridden with a real mock later.

Bumps [aws-sdk](https://github.com/aws/aws-sdk-js) from 2.854.0 to 2.858.0.
- [Release notes](https://github.com/aws/aws-sdk-js/releases)
- [Changelog](https://github.com/aws/aws-sdk-js/blob/master/CHANGELOG.md)
- [Commits](https://github.com/aws/aws-sdk-js/compare/v2.854.0...v2.858.0)
Signed-off-by: dependabot[bot] <support@github.com>

Bumps [postcss](https://github.com/postcss/postcss) from 8.2.6 to 8.2.7.
- [Release notes](https://github.com/postcss/postcss/releases)
- [Changelog](https://github.com/postcss/postcss/blob/main/CHANGELOG.md)
- [Commits](https://github.com/postcss/postcss/compare/8.2.6...8.2.7)
Signed-off-by: dependabot[bot] <support@github.com>

Bumps [exorcist](https://github.com/thlorenz/exorcist) from 1.0.1 to 2.0.0.
- [Release notes](https://github.com/thlorenz/exorcist/releases)
- [Commits](https://github.com/thlorenz/exorcist/compare/v1.0.1...v2.0.0)
Signed-off-by: dependabot[bot] <support@github.com>

Bumps [autoprefixer](https://github.com/postcss/autoprefixer) from 10.2.4 to 10.2.5.
- [Release notes](https://github.com/postcss/autoprefixer/releases)
- [Changelog](https://github.com/postcss/autoprefixer/blob/main/CHANGELOG.md)
- [Commits](https://github.com/postcss/autoprefixer/compare/10.2.4...10.2.5)
Signed-off-by: dependabot[bot] <support@github.com>

Bumps [@octokit/rest](https://github.com/octokit/rest.js) from 18.3.1 to 18.3.4.
- [Release notes](https://github.com/octokit/rest.js/releases)
- [Commits](https://github.com/octokit/rest.js/compare/v18.3.1...v18.3.4)
Signed-off-by: dependabot[bot] <support@github.com>

Bumps [typescript](https://github.com/Microsoft/TypeScript) from 4.2.2 to 4.2.3.
- [Release notes](https://github.com/Microsoft/TypeScript/releases)
- [Commits](https://github.com/Microsoft/TypeScript/compare/v4.2.2...v4.2.3)
Signed-off-by: dependabot[bot] <support@github.com>

Bumps [eslint-plugin-mocha](https://github.com/lo1tuma/eslint-plugin-mocha) from 8.0.0 to 8.1.0.
- [Release notes](https://github.com/lo1tuma/eslint-plugin-mocha/releases)
- [Changelog](https://github.com/lo1tuma/eslint-plugin-mocha/blob/master/CHANGELOG.md)
- [Commits](https://github.com/lo1tuma/eslint-plugin-mocha/compare/8.0.0...8.1.0)
Signed-off-by: dependabot[bot] <support@github.com>

Bumps [axe-core](https://github.com/dequelabs/axe-core) from 4.1.2 to 4.1.3.
- [Release notes](https://github.com/dequelabs/axe-core/releases)
- [Changelog](https://github.com/dequelabs/axe-core/blob/develop/CHANGELOG.md)
- [Commits](https://github.com/dequelabs/axe-core/compare/v4.1.2...v4.1.3)
Signed-off-by: dependabot[bot] <support@github.com>

Bumps [mocha](https://github.com/mochajs/mocha) from 8.3.0 to 8.3.1.
- [Release notes](https://github.com/mochajs/mocha/releases)
- [Changelog](https://github.com/mochajs/mocha/blob/master/CHANGELOG.md)
- [Commits](https://github.com/mochajs/mocha/compare/v8.3.0...v8.3.1)
Signed-off-by: dependabot[bot] <support@github.com>

The @hypothesis/frontend-shared lives now in another repo. The
recommended way to test the package in the context of the client is
using yalc. Therefore, it is better to ignores yalc related files so
they are not committed by mistake.

Bumps [chai](https://github.com/chaijs/chai) from 4.3.1 to 4.3.3.
- [Release notes](https://github.com/chaijs/chai/releases)
- [Changelog](https://github.com/chaijs/chai/blob/main/History.md)
- [Commits](https://github.com/chaijs/chai/compare/4.3.1...4.3.3)
Signed-off-by: dependabot[bot] <support@github.com>

Check that non-empty tags are assigned when expected.

`createAnnotation` used to accept a partially filled-out annotation
object with arbitrary properties. However the argument was only ever
used to set the `$highlight` flag. Therefore we can simplify the
interface by making the method accept just a `highlight` flag instead.

 - Simplify `createAnnotation` argument

 - Add tests for handling of `highlight` option to `createAnnotation`

 - Remove the `createHighlight` method in guest as it was just a trivial
   wrapper around `createAnnotation({ highlight: true })`

Add missing tests for this critical property of new annotations. In the
process revise some variable names in `createAnnotation` that were
misleading.

Add tests for the main code paths in `Guest` that call `createAnnotation`.

Convert the `createAnnotation` method of `Guest` to use async/await
instead of manual chaining of Promise operations. This makes it easier
to follow the logic and see that document metadata is assigned to the
annotation before it is broadcast to other parts of the annotator in the
`beforeAnnotationCreated` event. It also makes it easier to external
code (eg. the tests) to determine when `createAnnotation` is "done" and
has finished updating the annotation.

 - Convert `Guest#createAnnotation` to use async/await

 - Update tests for `createAnnotation` to await the returned Promise
   instead of a fixed timeout

 - Add a missing check in `createAnnotation` tests for the argument
   passed to the `beforeAnnotationCreated` event

Open links to documents in a new tab. This is important in the Notebook
view at present to "escape" the Notebook's frame, but makes sense in
all contexts as it more closely adheres to our pattern of opening links
to external properties in new windows.

Make sure document titles that are not linked don't look like links.

Make `AnnotationTimestamps` align with changes to `ShowDocumentInfo`;
it is now a dumb component. Centralize logic in `AnnotationHeader`.

- Refactor `ShowDocumentInfo`: don't link to documents for third-party
  annotations. This is a possibly-temporary measure to prevent linking
  to documents that are not directly accessible, e.g. in an LMS context.
- Remove unnecessary forwarding of `showDocumentInfo` through several
  components.
- Centralize some logic in `AnnotationHeader` and make `ShowDocumentInfo`
  a dumb component.

These changes enforce that the bucket-bar is destroyed and allows
multiple creations of the bucket bar, if needed.

The sidebar is not the only other frame that may be interested in new
annotations. The notebook is too.

 - Extract the repeated logic for checking the data passed to the
   event's callback into a `createCallback` helper

 - Add separate tests for HTML and PDF documents

 - Add test for the error path when getting the URL of a PDF fails

Replace the "plugin" functionality in the Guest that indirectly
instantiates the `DocumentMeta`, `PDF` and `CrossFrame` classes with
direct instantiation of those classes.

The annotator part of the Hypothesis client is no longer a pluggable
toolbox which can be arbitrarily extended by user-provided plugins.
Removing the "plugins" logic and replacing it with direct construction
of the necessary classes removes a lot of indirection that made the code
harder to follow and also makes it easier for TypeScript to statically
check the code. It will also enable the `config` object that is passed
to `Guest` to be paired down to just the fields that are actually needed
and properly typed.

In future we will need some kind of plugin/integration facility to
support different document viewers. For we will build a more specific
document type integration facility when the time comes.

 - Remove `this.plugins` field from `Guest` class and `pluginClasses`
   config and replace with direct construction of `PDFIntegration`,
   `DocumentMeta` and `CrossFrame` classes

 - Update the `AnchoringImpl` typedef to correctly reflect that some anchoring
   implementations (HTML) have a synchronous `describe` method

 - Remove unnecessary `config` argument to `PDF` constructor

 - Replace the `PDF: {}` content in the guest config with `documentType:
   'pdf'` as a more obvious way for the annotator entry point to
   configure which document viewer integration is loaded. In future we
   can generalize this to support different types of viewer integration.

This PR prevents scrolling of the body of the host when the notebook is
opened.

Reported
[here](https://github.com/hypothesis/client/pull/3024#pullrequestreview-592240569).

This solution doesn't work for iOS < 13.

- made the button stick on the top without taking space from the
  notebook. I re-enabled the original padding of the notebook.

- fixed an issue with window resizing that caused the notebook to
  disappear.

- on touch devices closing the notebook, closed the sidebar too.