Title: #796: ci: enable sssd-ci for 1-16 branch
It is on purpose. The reason is in the pull request description: Fedora 28 is the latest
version that contains SSSD 1.16. Fedora 29+ contains SSSD 2.0, thus I do not think it is
necessary to run 1.16 test on those distros. But if you think it is meaningful, it is easy
to add it here as well.
See the full comment at https://github.com/SSSD/sssd/pull/796#issuecomment-479853165