Merge branch '414529-add-ticket-ff' into 'master'

Add feature flag for service desk ticket type

See merge request https://gitlab.com/gitlab-org/gitlab/-/merge_requests/124681



Merged-by: Peter Leitzen <pleitzen@gitlab.com>
Approved-by: Peter Leitzen <pleitzen@gitlab.com>
Reviewed-by: Peter Leitzen <pleitzen@gitlab.com>
Reviewed-by: Rajendra Kadam <rkadam@gitlab.com>
Co-authored-by: Rajendra Kadam <rkadam@gitlab.com>