fix(接口测试): 修复引用步骤中添加等待控制器执行不生效问题

--bug=1024135 --user=赵勇 【接口测试】场景中引用的用例，添加等待时间无效 https://www.tapd.cn/55049933/s/1347635

backend/src/main/java/io/metersphere/api/dto/definition/request/ElementUtil.java

@@ -478,7 +478,8 @@ public class ElementUtil {
                             Collectors.toCollection(() -> new TreeSet<>(Comparator.comparing(MsTestElement::getId))),
                             ArrayList::new));
 
-            element.setHashTree((LinkedList<MsTestElement>) sourceList);
+            element.getHashTree().clear();
+            element.getHashTree().addAll(sourceList);
         } catch (Exception e) {
             element.setHashTree(targetHashTree);
         }