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/wms-custom-tilegrid-512x256.js

@@ -1,12 +1,11 @@
 import Map from '../src/ol/Map.js';
-import View from '../src/ol/View.js';
-import {getWidth} from '../src/ol/extent.js';
-import TileLayer from '../src/ol/layer/Tile.js';
-import {get as getProjection} from '../src/ol/proj.js';
 import OSM from '../src/ol/source/OSM.js';
-import TileWMS from '../src/ol/source/TileWMS.js';
 import TileGrid from '../src/ol/tilegrid/TileGrid.js';
-
+import TileLayer from '../src/ol/layer/Tile.js';
+import TileWMS from '../src/ol/source/TileWMS.js';
+import View from '../src/ol/View.js';
+import {get as getProjection} from '../src/ol/proj.js';
+import {getWidth} from '../src/ol/extent.js';
 
 const projExtent = getProjection('EPSG:3857').getExtent();
 const startResolution = getWidth(projExtent) / 256;
@@ -17,27 +16,27 @@ for (let i = 0, ii = resolutions.length; i < ii; ++i) {
 const tileGrid = new TileGrid({
   extent: [-13884991, 2870341, -7455066, 6338219],
   resolutions: resolutions,
-  tileSize: [512, 256]
+  tileSize: [512, 256],
 });
 
 const layers = [
   new TileLayer({
-    source: new OSM()
+    source: new OSM(),
   }),
   new TileLayer({
     source: new TileWMS({
       url: 'https://ahocevar.com/geoserver/wms',
       params: {'LAYERS': 'topp:states', 'TILED': true},
       serverType: 'geoserver',
-      tileGrid: tileGrid
-    })
-  })
+      tileGrid: tileGrid,
+    }),
+  }),
 ];
 const map = new Map({
   layers: layers,
   target: 'map',
   view: new View({
     center: [-10997148, 4569099],
-    zoom: 4
-  })
+    zoom: 4,
+  }),
 });