add case about force stop leader of cluster

tests/system-test/6-cluster/vnode/4dnode1mnode_basic_replica3_insertdatas_stop_leader.py

@@ -389,7 +389,7 @@ class TDTestCase:
                     if role==self.stop_dnode_id:
 
                         if vgroup_info[ind+1] =="offline" and "leader" in vgroup_info:
-                            tdLog.info(" === revote leader ok , leader is {} now   ====".format(list(vgroup_info).index("leader")-1))
+                            tdLog.info(" === revote leader ok , leader is {} now   ====".format(vgroup_info[list(vgroup_info).index("leader")-1]))
                             check_status = True
                         elif vgroup_info[ind+1] !="offline":
                             tdLog.info(" === dnode {} should be offline ".format(self.stop_dnode_id))