Fix f-strings variable error (#6677)

dolphinscheduler-python/pydolphinscheduler/examples/bulk_create.py

@@ -40,12 +40,12 @@ for wf in range(0, NUM_WORKFLOWS):
 
     with ProcessDefinition(name=workflow_name, tenant=TENANT) as pd:
         for t in range(0, NUM_TASKS):
-            task_name = f"task:{t}-workflow:{wf}"
+            task_name = f"task:{t}-{workflow_name}"
             command = f"echo This is task {task_name}"
             task = Shell(name=task_name, command=command)
 
             if IS_CHAIN and t > 0:
-                pre_task_name = f"task:{t-1}-wf:{wf}"
+                pre_task_name = f"task:{t-1}-{workflow_name}"
                 pd.get_one_task_by_name(pre_task_name) >> task
 
         # We just submit workflow and task definition without set schedule time or run it manually