What you need to do depends on your setup.
For an CMK enterprise with agent bakery you “only” need to bake and sign the agents and after some time all registered agents should have the right configuration.
For the RAW edition or Enterprise without bakery you need to adjust the “check_mk.user.yml” and replace this file on the installed agents manually or with the help of some software management. Reload the agent config and the message should be gone.