Don't upgrade centos-9-stream repos in the Schutzfile, the newer ones
are broken. Considering CI is broken on main right now, that takes
priority, fixing centos-9 can be done in a followup.
- Add ppc64le and s390x repo URLs to Fedora repositories.
- Add Fedora 40 (rawhide) repositories.
- Update Fedora testing repositories to latest snapshots, adding new
arches and F40 repos. Basically took what is in osbuild/images repo.
Signed-off-by: Tomáš Hozza <thozza@redhat.com>