PR-CI: Add gating tests to nightly_[master, f28, rawhide]
    
    The objective of this change is to address the problem mentioned in this
    thread: https://lists.fedorahosted.org/archives/list/freeipa-devel@lists.fedorahosted.org/message/FIOWT53LJMAZQYHOTT4BEAJX5Q6422LB/
    
    Since the concept of nightly is being a superset of gating, the gating
    tests are incorporated in nightly in this commit.
    
    Fixes: https://pagure.io/freeipa/issue/7788
    
    Signed-off-by: Diogo Nunes <dnunes@redhat.com>
    Reviewed-By: Florence Blanc-Renaud <frenaud@redhat.com>
    Reviewed-By: Christian Heimes <cheimes@redhat.com>
    Reviewed-By: Francisco Trivino <ftrivino@redhat.com>