fix: #1586 deleting an image causes the editor to enter a bad state

Author: LucasXu0

frontend/app_flowy/packages/appflowy_editor/example/lib/pages/simple_editor.dart

@@ -30,6 +30,9 @@ class SimpleEditor extends StatelessWidget {
               ),
             ),
           );
+          editorState.logConfiguration
+            ..handler = debugPrint
+            ..level = LogLevel.all;
           onEditorStateChange(editorState);
 
           return AppFlowyEditor(

frontend/app_flowy/packages/appflowy_editor/lib/src/render/image/image_node_widget.dart

@@ -91,7 +91,7 @@ class _ImageNodeWidgetState extends State<ImageNodeWidget>
 
   @override
   Position end() {
-    return Position(path: widget.node.path, offset: 1);
+    return start();
   }
 
   @override