Mysql 8.0.22 master slave replication: why slave is trying to create user

I am following this repo (https://github.com/alexanderfefelov/docker-mysql-replication) to setup one master one slave replication. I am not able to get it working. The master seems to be OK, but the slave has the following error:

mysql_slave1.1.ydo3yuvbyibc@64g-480g-node2    | 2020-12-22T23:19:42.284061Z 0 [System] [MY-010931] [Server] /usr/sbin/mysqld: ready for connections. Version: '8.0.22'  socket: '/var/run/mysqld/mysqld.sock'  port: 3306  MySQL Community Server - GPL.
mysql_slave1.1.ydo3yuvbyibc@64g-480g-node2    | 2020-12-22T23:19:42.285009Z 5 [System] [MY-010562] [Repl] Slave I/O thread for channel '': connected to master 'replicator@mysql_master:3306',replication started in log 'log-bin.000023' at position 156
mysql_slave1.1.ydo3yuvbyibc@64g-480g-node2    | 2020-12-22T23:19:42.289356Z 6 [ERROR] [MY-010584] [Repl] Slave SQL for channel '': Error 'Operation CREATE USER failed for 'replicator'@'%'' on query. Default database: ''. Query: 'CREATE USER 'replicator'@'%' IDENTIFIED WITH 'mysql_native_password' AS '*2470C0C06DEE42FD1618BB99005ADCA2EC9D1E19'', Error_code: MY-001396
mysql_slave1.1.ydo3yuvbyibc@64g-480g-node2    | 2020-12-22T23:19:42.289425Z 6 [Warning] [MY-010584] [Repl] Slave: Operation CREATE USER failed for 'replicator'@'%' Error_code: MY-001396
mysql_slave1.1.ydo3yuvbyibc@64g-480g-node2    | 2020-12-22T23:19:42.289442Z 6 [ERROR] [MY-010586] [Repl] Error running query, slave SQL thread aborted. Fix the problem, and restart the slave SQL thread with "SLAVE START". We stopped at log 'log-bin.000016' position 3107328

The master already created user replicator during start up, why slave also tries to create this user?

Thanks!