fix(接口测试): 修复复制的mock无法保存成功的缺陷

--bug=1041111 --user=王孝刚 【接口测试】mock列表-复制mock成功-编辑复制的mock-保存失败
https://www.tapd.cn/55049933/s/1521214

frontend/src/views/api-test/management/components/management/mock/mockTable.vue

@@ -678,6 +678,7 @@
 
   function editMock(record: ApiDefinitionMockDetail) {
     isEdit.value = true;
+    isCopy.value = false;
     openMockDetailDrawer(record);
   }