Removing replica-s4u2proxy.ldif since it's not used anymore
    
    Since commit 23a0453c4d33271376b2156f2e2b484e8b9708c9, the
    replica-s4u2proxy.ldif file it's not used anymore.
    
    https://pagure.io/freeipa/issue/7174
    
    Reviewed-By: Rob Crittenden <rcritten@redhat.com>