feat: use React.lazy for loading components (#158)

src/router.tsx

@@ -5,16 +5,15 @@ import { Router, Route, Switch } from 'react-router-dom';
 import { createBrowserHistory } from 'history';
 import { AppContextConsumer, AppStateInterface } from './App/App';
 
-import { asyncComponent } from './utils/asyncComponent';
 import Header from './components/Header';
 
 const history = createBrowserHistory({
   basename: window.__VERDACCIO_BASENAME_UI_OPTIONS && window.__VERDACCIO_BASENAME_UI_OPTIONS.url_prefix,
 });
 
-const NotFound = asyncComponent(() => import('./components/NotFound'));
-const VersionPackage = asyncComponent(() => import('./pages/Version'));
-const HomePage = asyncComponent(() => import('./pages/home'));
+const NotFound = React.lazy(() => import('./components/NotFound'));
+const VersionPackage = React.lazy(() => import('./pages/Version'));
+const HomePage = React.lazy(() => import('./pages/home'));
 
 interface RouterAppProps {
   onLogout: () => void;
@@ -25,7 +24,7 @@ class RouterApp extends Component<RouterAppProps> {
   public render(): ReactElement<HTMLDivElement> {
     return (
       <Router history={history}>
-        <>
+        <React.Suspense fallback={null}>
           {this.renderHeader()}
           <Switch>
             <Route exact={true} path={'/'} render={this.renderHomePage} />
@@ -35,7 +34,7 @@ class RouterApp extends Component<RouterAppProps> {
             <Route exact={true} path={'/-/web/detail/@:scope/:package/v/:version'} render={this.renderVersionPage} />
             <Route component={NotFound} />
           </Switch>
-        </>
+        </React.Suspense>
       </Router>
     );
   }