How to migrate "db2_backup_created" mattemost settings

Hello,

I’ve upgraded today Gitlab CE from 10.3.0 to 10.3.3. At the end of the upgrade I received this notification:

* Mattermost
        Detected deprecated Mattermost settings. Starting with GitLab 11.0, these settings are no longer supported.
        Check http://docs.gitlab.com/omnibus/gitlab-mattermost/#upgrading-gitlab-mattermost-from-versions-prior-to-11-0 for details. 

        * mattermost['db2_backup_created']
        * mattermost['db2_team_name']
        * ... many more settings here

I’ve succeeded in migrating the “many more settings” to the new mattermost[env] = { 'MM_...' => '...' } scheme however I couldn’t find how to migrate those two mentioned above. Any idea?

PS: the AI that checks the topic title sucks dick. It took me a lot of time to create a title where it would shut up.

I’ve removed those two settings without loss. No more warnings get issued at service (re)start.