fix(测试计划): 修复功能用例列表排序报错

--bug=1042477 --user=王旭 【测试计划】-功能用例列表排序报错 https://www.tapd.cn/55049933/s/1531342

backend/services/test-plan/src/main/java/io/metersphere/plan/controller/TestPlanFunctionalCaseController.java

@@ -66,7 +66,7 @@ public class TestPlanFunctionalCaseController {
     @CheckOwner(resourceId = "#request.getTestPlanId()", resourceType = "test_plan")
     public Pager<List<TestPlanCasePageResponse>> page(@Validated @RequestBody TestPlanCaseRequest request) {
         Page<Object> page = PageHelper.startPage(request.getCurrent(), request.getPageSize(),
-                StringUtils.isNotBlank(request.getSortString("id", "test_plan_functional_case")) ? request.getSortString("id", "test_plan_functional_case") : "test_plan_functional_case.pos asc");
+                StringUtils.isNotBlank(request.getSortString("id", "functional_case")) ? request.getSortString("id", "functional_case") : "test_plan_functional_case.pos asc");
 
         return PageUtils.setPageInfo(page, testPlanFunctionalCaseService.getFunctionalCasePage(request, false));
     }