Fix warnings in docker-compose.yml setup

See merge request https://gitlab.com/gitlab-org/build/CNG/-/merge_requests/2003



Merged-by: Jason Plum <jplum@gitlab.com>
Approved-by: Clemens Beck <cbeck@gitlab.com>
Approved-by: Jason Plum <jplum@gitlab.com>
Reviewed-by: Clemens Beck <cbeck@gitlab.com>
Co-authored-by: Balasankar "Balu" C <balasankar@gitlab.com>