neon: use helper methods to find active application

packages/neon/neon/lib/src/router.dart

@@ -105,7 +105,7 @@ class NextcloudAppSettingsRoute extends GoRouteData {
   @override
   Widget build(final BuildContext context, final GoRouterState state) {
     final appImplementations = Provider.of<List<AppImplementation>>(context, listen: false);
-    final appImplementation = appImplementations.firstWhere((final app) => app.id == appid);
+    final appImplementation = appImplementations.find(appid)!;
 
     return NextcloudAppSettingsPage(appImplementation: appImplementation);
   }