Added service worker back to the project to recover PWA capabilities

src/index.tsx

@@ -5,6 +5,7 @@ import { homepage } from '../package.json';
 import container from './container';
 import store from './container/store';
 import { fixLeafletIcons } from './utils/helpers/leaflet';
+import * as serviceWorkerRegistration from './serviceWorkerRegistration';
 import 'react-datepicker/dist/react-datepicker.css';
 import 'leaflet/dist/leaflet.css';
 import './index.scss';
@@ -26,3 +27,8 @@ render(
   </Provider>,
   document.getElementById('root'),
 );
+
+// If you want your app to work offline and load faster, you can change
+// unregister() to register() below. Note this comes with some pitfalls.
+// Learn more about service workers: https://cra.link/PWA
+serviceWorkerRegistration.register();