修改mysql用户的时候报错ERROR 1396 (HY000): Operation ALTER USER failed for ‘root‘@‘localhost‘

参考：https://blog.csdn.net/q258523454/article/details/84555847

mysql连数据库的时候报错:

1251 client does not support authentication protocol requested by server;consider upgrading Mysql client

ERROR 1396 (HY000): Operation ALTER USER failed for ‘root’@’localhost’

先登录mysql