httpinstance: add ipa-ca.$DOMAIN alias in initial request
    
    For detailed discussion on the purpose of this change and the design
    decisions made, see `git log -1 $THIS_COMMIT~2`.
    
    For new server/replica installation, issue the HTTP server
    certificate with the 'ipa-ca.$DOMAIN' SAN dNSName.  This is
    accomplished by adding the name to the Certmonger tracking request.
    
    Part of: https://pagure.io/freeipa/issue/8186
    
    Reviewed-By: Rob Crittenden <rcritten@redhat.com>