Merge branch 'bug/44103-ie11-compatibility' into 'master'

Array.fill polyfill for IE 11 compatibility.

Closes #44103

See merge request gitlab-org/gitlab-ce!17897

app/assets/javascripts/commons/polyfills.js

 // ECMAScript polyfills
+import 'core-js/fn/array/fill';
 import 'core-js/fn/array/find';
 import 'core-js/fn/array/find-index';
 import 'core-js/fn/array/from';