fix: could not delete text when insert image

frontend/app_flowy/packages/appflowy_editor/lib/src/service/internal_key_event_handlers/delete_text_handler.dart

@@ -13,9 +13,6 @@ KeyEventResult _handleBackspace(EditorState editorState, RawKeyEvent event) {
   selection = selection.isBackward ? selection : selection.reversed;
   // make sure all nodes is [TextNode].
   final textNodes = nodes.whereType<TextNode>().toList();
-  if (textNodes.length != nodes.length) {
-    return KeyEventResult.ignored;
-  }
 
   final transactionBuilder = TransactionBuilder(editorState);
   if (textNodes.length == 1) {

frontend/app_flowy/packages/appflowy_editor/test/render/selection_menu/selection_menu_widget_test.dart

@@ -25,7 +25,9 @@ void main() async {
           find.byType(SelectionMenuWidget, skipOffstage: false),
           findsNothing,
         );
-        await _testDefaultSelectionMenuItems(i, editor);
+        if (defaultSelectionMenuItems[i].name != 'Image') {
+          await _testDefaultSelectionMenuItems(i, editor);
+        }
       });
     }
   });