Explore gitlab and buildah multi-arch oci image support.

Just something that I stumbled across this weekend. Would simplify some things in the CI.

https://www.youtube.com/watch?v=SYJgkkjqd7s

It looks like gitlab registry has supported multi-arches for a while, but its not exposed in the gui anywhere.

https://gitlab.com/gitlab-org/gitlab/-/issues/23809

Another thing that needs to be looked at is if buildah is able to do multi-arch for docker images. And or if gitlab has full OCI support. By default I assume buidlah expects oci stuff, and gitlab is only expected to work with docker images.