fix(接口测试): 修复导入接口定义时接口用例ID格式不正确的问题

backend/src/main/java/io/metersphere/api/service/ApiDefinitionService.java

@@ -619,7 +619,7 @@ public class ApiDefinitionService {
         apiTestCase.setUpdateUserId(SessionUtils.getUserId());
         if (sameCase == null) {
             apiTestCase.setId(UUID.randomUUID().toString());
-            apiTestCase.setNum(getNextNum(apiTestCase.getApiDefinitionId()));
+            apiTestCase.setNum(apiTestCaseService.getNextNum(apiTestCase.getApiDefinitionId()));
             apiTestCase.setCreateTime(System.currentTimeMillis());
             apiTestCase.setUpdateTime(System.currentTimeMillis());
             apiTestCase.setCreateUserId(SessionUtils.getUserId());