Create a new test for rootless buildah, i.e. buildah running as a non-root user. We released an update that silently switched buildah from slirp4netns to pasta on SLES15, where pasta (package name passt) is not supposed to be available. This regression was not caught because we don't test rootless buildah, where this applies. For rootfull buildah, neither of those network backends are needed/used.

Acceptance criteria¶

• AC1: We have a new test runs that tests the basic buildah functions in rootless mode

Further references¶

• https://bugzilla.suse.com/show_bug.cgi?id=1232522
• https://suse.slack.com/archives/C02CGKBCGT1/p1730263234424149