Merge branch '397138-metrics-dashboard-concern' into 'master'

Remove grafana api controller and metrics dashboard field

See merge request https://gitlab.com/gitlab-org/gitlab/-/merge_requests/125259



Merged-by: Vitali Tatarintev <vtatarintev@gitlab.com>
Approved-by: Vitali Tatarintev <vtatarintev@gitlab.com>
Approved-by: Paulina Sedlak-Jakubowska <psedlak-jakubowska@gitlab.com>
Approved-by: Marcin Sedlak-Jakubowski <msedlakjakubowski@gitlab.com>
Reviewed-by: Peter Leitzen <pleitzen@gitlab.com>
Reviewed-by: Rajendra Kadam <rkadam@gitlab.com>
Co-authored-by: Rajendra Kadam <rkadam@gitlab.com>