[Fix-13657][Master]NPE caused by the execution of workflow with startNode and forbidden task (#13668)

Co-authored-by: HomminLee <lihongmin@ysstech.com>

dolphinscheduler-master/src/main/java/org/apache/dolphinscheduler/server/master/runner/WorkflowExecuteRunnable.java

@@ -1513,8 +1513,11 @@ public class WorkflowExecuteRunnable implements Callable<WorkflowSubmitStatue> {
      */
     private void setIndirectDepList(String taskCode, List<String> indirectDepCodeList) {
         TaskNode taskNode = dag.getNode(taskCode);
-        List<String> depCodeList = taskNode.getDepList();
-        for (String depsNode : depCodeList) {
+        // If workflow start with startNode or recoveryNode, taskNode may be null
+        if (taskNode == null) {
+            return;
+        }
+        for (String depsNode : taskNode.getDepList()) {
             if (forbiddenTaskMap.containsKey(Long.parseLong(depsNode))) {
                 setIndirectDepList(depsNode, indirectDepCodeList);
             } else {