Add s390x Artifacts

[Rurouni-Jiaxin]

What this PR does / why we need it:

I create this PR as part of the bigger effort to enable KubeVirt on s390x, a.k.a IBM Z ( please refer to : https://github.com/kubevirt/kubevirt/pull/10490 ). It appears that https://github.com/kubevirt/common-instancetypes/ depends on containerdisks.

Therefore I added "s390x" entries to existing Feodora, CentOS Stream and Ubuntu Artifact / registries.

I have not added any tests to either artifacts/fedora/fedora_test.go , artifacts/centosstream/centos-stream_test.go, or artifacts/ubuntu/ubuntu_test.go, because the tests appears to only verify the parsing function.

TO DO:

Discuss whether other Linux distros, e.g. OpenSUSE is needed for s390x.

Special notes for your reviewer:

Release note: