Merge branch 'rodrigo/remove-user-mapping-ff-from-controller' into 'master'

Remove importer_user_mapping FF check from controller and job

See merge request https://gitlab.com/gitlab-org/gitlab/-/merge_requests/167354



Merged-by: Rodrigo Tomonari <rtomonari@gitlab.com>
Approved-by: James Nutt <jnutt@gitlab.com>