There is a new prototype being prototyped for our compose testing. (Thank you carofe!)

Let's get it running in the testing Jenkins!

Initially it'll run on the side, it won't fail the main "all tests" job. And we'll take it from there.

We need to agree from what repo we'll pull the test suite. Should I make one in GitLab under CentOS Stream? Or do we want to use a repo in the Integration SIG namespace? (I'll ask the same question in the thread: https://discussion.fedoraproject.org/t/contributing-compose-tests-to-centos-stream/92934/15)