Client shows `utf8mb3` csname replace warning message while logging into server

$ /test/GAL_MD150621-mariadb-10.6.2-linux-x86_64-dbg/bin/mysql -A -uroot -S/test/GAL_MD150621-mariadb-10.6.2-linux-x86_64-dbg/node1/node1_socket.sock

/test/GAL_MD150621-mariadb-10.6.2-linux-x86_64-dbg/bin/mysql: Warning: Charset id '33' csname 'utf8' trying to replace existing csname 'utf8mb3'

/test/GAL_MD150621-mariadb-10.6.2-linux-x86_64-dbg/bin/mysql: Warning: Charset id '83' csname 'utf8' trying to replace existing csname 'utf8mb3'

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