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.

examples/static-image.js

@@ -1,10 +1,9 @@
-import Map from '../src/ol/Map.js';
-import View from '../src/ol/View.js';
-import {getCenter} from '../src/ol/extent.js';
 import ImageLayer from '../src/ol/layer/Image.js';
+import Map from '../src/ol/Map.js';
 import Projection from '../src/ol/proj/Projection.js';
 import Static from '../src/ol/source/ImageStatic.js';
-
+import View from '../src/ol/View.js';
+import {getCenter} from '../src/ol/extent.js';
 
 // Map views always need a projection.  Here we just want to map image
 // coordinates directly to map coordinates, so we create a projection that uses
@@ -13,7 +12,7 @@ const extent = [0, 0, 1024, 968];
 const projection = new Projection({
   code: 'xkcd-image',
   units: 'pixels',
-  extent: extent
+  extent: extent,
 });
 
 const map = new Map({
@@ -23,15 +22,15 @@ const map = new Map({
         attributions: '© <a href="http://xkcd.com/license.html">xkcd</a>',
         url: 'https://imgs.xkcd.com/comics/online_communities.png',
         projection: projection,
-        imageExtent: extent
-      })
-    })
+        imageExtent: extent,
+      }),
+    }),
   ],
   target: 'map',
   view: new View({
     projection: projection,
     center: getCenter(extent),
     zoom: 2,
-    maxZoom: 8
-  })
+    maxZoom: 8,
+  }),
 });