Comment 1 for bug 2051693

This looks to be one to raise internally inside Canonical. Fix likely around https://github.com/canonical/mysql-router-k8s-operator/blob/fad69b1423582ebcaf579a5b2c0be4979283838a/src/mysql_shell.py#L107 change the user creation to include IDENTIFIED WITH caching_sha2_password BY 'auth_string'... or to set caching_sha2_password as the default in the mysql container.