chore(mobile): remove unused import

mobile/lib/modules/asset_viewer/services/image_viewer.service.dart

@@ -1,6 +1,5 @@
 import 'dart:io';
 
-import 'package:flutter/foundation.dart';
 import 'package:hooks_riverpod/hooks_riverpod.dart';
 import 'package:immich_mobile/shared/models/asset.dart';
 import 'package:immich_mobile/shared/providers/api.provider.dart';