Enable Prettier for code other than PDF.js in dev-server/static/scripts/

We only want to exclude the vendored PDF.js code from Prettier formatting. The
other small scripts in dev-server/static/scripts/ should be formatted.

.prettierignore

-**/vendor/*
 .*/**
 build/
 coverage/
 docs/
-dev-server/static/*
-lib/
+dev-server/static/scripts/pdfjs/*

dev-server/static/scripts/index.js

- /**
+/**
  * Because the code in this file is not transpiled by Babel, it must be compatible
  * with all the supported browsers version (see `browserlist` in `package.json`)
  * without transpilation. Do not include latest EcmaScript features as these
@@ -24,11 +24,18 @@
   };
 
   // Set up links whose URLs should have a randomly generated suffix.
-  const randomizedLinks = Array.from(document.querySelectorAll('.js-randomize-url'));
+  const randomizedLinks = Array.from(
+    document.querySelectorAll('.js-randomize-url')
+  );
   for (let link of randomizedLinks) {
     const randomizeUrl = () => {
-      const randomHexString = Math.random().toString().slice(2 /* strip "0." prefix */, 6);
-      link.href = link.href.replace(/(\/rand-.*)?$/, `/rand-${randomHexString}`);
+      const randomHexString = Math.random()
+        .toString()
+        .slice(2 /* strip "0." prefix */, 6);
+      link.href = link.href.replace(
+        /(\/rand-.*)?$/,
+        `/rand-${randomHexString}`
+      );
     };
     randomizeUrl();
     link.addEventListener('click', randomizeUrl);

dev-server/static/scripts/util.js

- /**
+/**
  * Because the code in this file is not transpiled by Babel, it must be compatible
  * with all the supported browsers version (see `browserlist` in `package.json`)
  * without transpilation. Do not include latest EcmaScript features as these
@@ -27,7 +27,9 @@ function loadClient(clientUrl) {
  * This uses the same method as the browser extension does to deactivate the client.
  */
 function unloadClient() {
-  let annotatorLink = document.querySelector('link[type="application/annotator+html"]');
+  let annotatorLink = document.querySelector(
+    'link[type="application/annotator+html"]'
+  );
 
   if (annotatorLink) {
     annotatorLink.dispatchEvent(new Event('destroy'));