报错：
nodejs.ER_NOT_SUPPORTED_AUTH_MODEError: ER_NOT_SUPPORTED_AUTH_MODE: Client does not support authentication protocol requested by server; consider upgrading MySQL client
mysql版本
8.0.16
解决：
$ mysql -u root -p > use mysql; > alter user 'root'@'localhost' identified with mysql_native_password by '123456'; > flush privileges;
注意：123456是连接数据库的密码
参考：
Error: ER_NOT_SUPPORTED_AUTH_MODE: Client does not support authentication protocol requested by serv
