fix warning

mobile/lib/presentation/pages/editing/drift_crop.page.dart

@@ -1,3 +1,5 @@
+import 'dart:async';
+
 import 'package:auto_route/auto_route.dart';
 import 'package:crop_image/crop_image.dart';
 import 'package:easy_localization/easy_localization.dart';
@@ -34,7 +36,7 @@ class DriftCropImagePage extends HookWidget {
             icon: Icon(Icons.done_rounded, color: context.primaryColor, size: 24),
             onPressed: () async {
               final croppedImage = await cropController.croppedImage();
-              context.pushRoute(DriftEditImageRoute(asset: asset, image: croppedImage, isEdited: true));
+              unawaited(context.pushRoute(DriftEditImageRoute(asset: asset, image: croppedImage, isEdited: true)));
             },
           ),
         ],