When store modules were refactored to only receive their local state in
selectors, the code in `store/modules/real-time-updates` which directly
uses selectors from other modules rather than calling
`store.<selectorMethod>(...)` was not updated to pass in the appropriate
part of the state.

Fixing this resolves two problems:

 - An error when processing notifications of deleted annotations from
   the server. These notifications are currently not getting delivered
   due to a server-side issue (see https://github.com/hypothesis/h/pull/6214).

 - Filtering notifications of new or updated annotations not excluding
   annotations from groups that are not currently focused.

   Fixing this second issue has the side effect that it _appears_ to fix
   https://github.com/hypothesis/support/issues/137 from the user's
   point of view. I say _appears to_ because the backend is still
   incorrectly delivering notifications that the user shouldn't be able
   to see. That is fixed by https://github.com/hypothesis/h/pull/6202