Create CNG tags for FIPS builds

What does this MR do and why?

When CNG branches are created with the -fips suffix, they will create images that are FIPS-compliant. These images are based on UBI-8, but the Go compiler is different: it dynamically links against a FIPS-validated OpenSSL.

This is needed to support release tags for gitlab-org/build/CNG!981 (merged).

Relates to gitlab-com/gl-infra/delivery#2418 (closed)

Author Check-list

• Has documentation been updated? Yes, see https://docs.gitlab.com/ee/development/fips_compliance.html#cloud-native-gitlab-cng.