ipatests: Fix TestReplicaPromotionLevel1
    
    A new test was added to TestReplicaPromotionLevel1 but was run
    after the replica uninstallation. As the new test checks
    the content of /etc/sssd/sssd.conf on the replica, merge it with the
    previous test, when the replica is still installed.
    
    Fixes: https://pagure.io/freeipa/issue/8414
    Reviewed-By: Mohammad Rizwan <myusuf@redhat.com>
    Reviewed-By: Rob Crittenden <rcritten@redhat.com>