Upgrade Web UI to Create-React-App 4 and React 17 (#1105)

* Upgrade to CRA 4.0.3

* Try to fix tests. No lucky

* Fix new ESLint errors

* Fix JS tests and remove unwanted dependency. (#1106)

* Fix tests

* Fix lint

* Remove React v16 workaround (fixed in v17)

* Force eslint to break on warnings

* Lint now needs to be called explicitly in the pipeline

Co-authored-by: Yash Jipkate <34203227+YashJipkate@users.noreply.github.com>

ui/src/store/createAdminStore.js

@@ -7,7 +7,7 @@ import throttle from 'lodash.throttle'
 import pick from 'lodash.pick'
 import { loadState, saveState } from './persistState'
 
-export default ({
+const createAdminStore = ({
   authProvider,
   dataProvider,
   history,
@@ -59,3 +59,5 @@ export default ({
   sagaMiddleware.run(saga)
   return store
 }
+
+export default createAdminStore