fix: unnecessary import

frontend/app_flowy/lib/workspace/presentation/plugins/grid/src/widgets/cell/cell_accessory.dart

@@ -1,6 +1,5 @@
 import 'package:flowy_infra/image.dart';
 import 'package:flowy_infra_ui/style_widget/hover.dart';
-import 'package:flutter/widgets.dart';
 import 'package:flowy_infra/theme.dart';
 import 'package:flutter/material.dart';
 import 'package:provider/provider.dart';