[bug] fix task definition delete (#7244)

Co-authored-by: edward-yang <yangjianh210@gmail.com>

dolphinscheduler-api/src/main/java/org/apache/dolphinscheduler/api/enums/Status.java

@@ -286,8 +286,8 @@ public enum Status {
     MOVE_PROCESS_TASK_RELATION_ERROR(50047, "move process task relation error", "移动任务到其他工作流错误"),
     DELETE_TASK_PROCESS_RELATION_ERROR(50048, "delete process task relation error", "删除工作流任务关系错误"),
     QUERY_TASK_PROCESS_RELATION_ERROR(50049, "query process task relation error", "查询工作流任务关系错误"),
-    TASK_DEFINE_STATE_ONLINE(50050, "task definition {0} is already on line", "任务定义[{0}]已上线"),
-    TASK_HAS_DOWNSTREAM(50051, "Task [{0}] exists downstream dependence", "任务[{0}]存在下游依赖"),
+    TASK_DEFINE_STATE_ONLINE(50050, "task definition [{0}] is already on line", "任务定义[{0}]已上线"),
+    TASK_HAS_DOWNSTREAM(50051, "Task exists downstream [{0}] dependence", "任务存在下游[{0}]依赖"),
     TASK_HAS_UPSTREAM(50052, "Task [{0}] exists upstream dependence", "任务[{0}]存在上游依赖"),
     MAIN_TABLE_USING_VERSION(50053, "the version that the master table is using", "主表正在使用该版本"),
     PROJECT_PROCESS_NOT_MATCH(50054, "the project and the process is not match", "项目和工作流不匹配"),

dolphinscheduler-api/src/main/java/org/apache/dolphinscheduler/api/service/impl/TaskDefinitionServiceImpl.java

@@ -211,7 +211,7 @@ public class TaskDefinitionServiceImpl extends BaseServiceImpl implements TaskDe
         int delete = taskDefinitionMapper.deleteByCode(taskCode);
         if (delete > 0) {
             List<ProcessTaskRelation> taskRelationList = processTaskRelationMapper.queryUpstreamByCode(projectCode, taskCode);
-            if (!processTaskRelationList.isEmpty()) {
+            if (!taskRelationList.isEmpty()) {
                 int deleteRelation = 0;
                 int deleteRelationLog = 0;
                 for (ProcessTaskRelation processTaskRelation : taskRelationList) {