Remove private additional properties

See merge request https://gitlab.com/gitlab-org/gitlab/-/merge_requests/167817



Merged-by: Pedro Pombeiro <noreply@pedro.pombei.ro>
Approved-by: Ankit Panchal <apanchal@gitlab.com>
Approved-by: Niko Belokolodov <nbelokolodov@gitlab.com>
Approved-by: Pedro Pombeiro <noreply@pedro.pombei.ro>
Reviewed-by: Pedro Pombeiro <noreply@pedro.pombei.ro>
Reviewed-by: Ankit Panchal <apanchal@gitlab.com>
Co-authored-by: Jonas Larsen <jlarsen@gitlab.com>