Add support for organization-wide agent CI authorization

See merge request !184259



Merged-by: Tiger Watson <twatson@gitlab.com>
Approved-by: Irina Bronipolsky <ibronipolsky@gitlab.com>
Approved-by: Terri Chu <tchu@gitlab.com>
Approved-by: Erick Bajao <fbajao@gitlab.com>
Approved-by: Daniele Rossetti <drossetti@gitlab.com>
Reviewed-by: Tiger Watson <twatson@gitlab.com>
Reviewed-by: Terri Chu <tchu@gitlab.com>
Reviewed-by: Daniele Rossetti <drossetti@gitlab.com>
Reviewed-by: Taka Nishida <tnishida@gitlab.com>
Reviewed-by: Irina Bronipolsky <ibronipolsky@gitlab.com>
Reviewed-by: Zachary Painter <zpainter@gitlab.com>