Add ci job that tests whether `yum install cta-release` works correctly.

We should have a pipeline stage that verifies whether the cta-release rpm package works correctly.

This job can be based on a simple runner that executes the following steps:

cat << EOF > /etc/yum.repos.d/cta-public-5.repo
[cta-public-5-alma9]
name=CERN Tape Archive
baseurl=https://cta-public-repo.web.cern.ch/testing/cta-5/el9/cta/x86_64/
enabled=1
gpgcheck=0
EOF

yum install cta-release

cta-versionlock config eos5
cta-versionlock apply

yum install cta-frontend
yum install cta-taped
yum install cta-rmcd
yum install cta-smc

yum install eos-server
yum install eos-client

Afterwards, check whether all the rpms were installed correctly.