feat:外来人员、跨单为修改适配

pjcloud-flow/pjcloud-flow-engine/pjcloud-flow-engine-biz/src/main/java/com/bsd/pjcloud/flow/engine/controller/EngineFlowController.java

@@ -304,7 +304,7 @@ public class EngineFlowController {
         long count = taskQuery.count();
         if (count != 1) {
             log.debug("queryAssignTaskOne查询错误,count!=1,processInstanceId:{}", processInstanceId);
-            return null;
+            return R.failed();
         }
         Task task = taskQuery.singleResult();
         String taskId = task.getId();