Merge branch 'security-prometheus-integration-mask-creds-15-9' into '15-9-stable-ee'

Mask Google IAP account details in Prometheus integration

See merge request https://gitlab.com/gitlab-org/security/gitlab/-/merge_requests/3081



Merged-by: GitLab Release Tools Bot <delivery-team+release-tools@gitlab.com>
Approved-by: Vitali Tatarintev <vtatarintev@gitlab.com>
Co-authored-by: Peter Leitzen <pleitzen@gitlab.com>