Make code prettier

This updates ESLint and our shared eslint-config-openlayers to use Prettier.  Most formatting changes were automatically applied with this:

    npm run lint -- --fix

A few manual changes were required:

 * In `examples/offscreen-canvas.js`, the `//eslint-disable-line` comment needed to be moved to the appropriate line to disable the error about the `'worker-loader!./offscreen-canvas.worker.js'` import.
 * In `examples/webpack/exapmle-builder.js`, spaces could not be added after a couple `function`s for some reason.  While editing this, I reworked `ExampleBuilder` to be a class.
 * In `src/ol/format/WMSGetFeatureInfo.js`, the `// @ts-ignore` comment needed to be moved down one line so it applied to the `parsersNS` argument.

test/spec/ol/events/event.test.js

@@ -1,48 +1,49 @@
-import Event, {preventDefault, stopPropagation} from '../../../../src/ol/events/Event.js';
+import Event, {
+  preventDefault,
+  stopPropagation,
+} from '../../../../src/ol/events/Event.js';
 
-describe('ol.events.Event', function() {
-
-  describe('constructor', function() {
-    it('takes a type as argument', function() {
+describe('ol.events.Event', function () {
+  describe('constructor', function () {
+    it('takes a type as argument', function () {
       const event = new Event('foo');
       expect(event.type).to.be('foo');
     });
-    it('does not set the propagationStopped flag', function() {
+    it('does not set the propagationStopped flag', function () {
       const event = new Event('foo');
       expect(event.propagationStopped).to.be(undefined);
     });
   });
 
-  describe('#preventDefault', function() {
-    it('sets the propagationStopped flag', function() {
+  describe('#preventDefault', function () {
+    it('sets the propagationStopped flag', function () {
       const event = new Event('foo');
       event.preventDefault();
       expect(event.propagationStopped).to.be(true);
     });
-    it('does the same as #stopPropagation', function() {
+    it('does the same as #stopPropagation', function () {
       const event = new Event('foo');
       expect(event.stopPropagation()).to.equal(event.preventDefault());
     });
   });
 
-  describe('ol.events.Event.preventDefault', function() {
-    it('calls preventDefault on the event object', function() {
+  describe('ol.events.Event.preventDefault', function () {
+    it('calls preventDefault on the event object', function () {
       const event = {
-        preventDefault: sinon.spy()
+        preventDefault: sinon.spy(),
       };
       preventDefault(event);
       expect(event.preventDefault.called).to.be(true);
     });
   });
 
-  describe('ol.events.Event.stopPropagation', function() {
-    it('calls preventDefault on the event object', function() {
+  describe('ol.events.Event.stopPropagation', function () {
+    it('calls preventDefault on the event object', function () {
       const event = {
-        stopPropagation: sinon.spy()
+        stopPropagation: sinon.spy(),
       };
       stopPropagation(event);
       expect(event.stopPropagation.called).to.be(true);
     });
   });
-
 });