Test --external-ca-type=ms-cs
    
    Verify that ipa-server-install with external CA and CA type ms-cs adds
    the correct extension to the CSR.
    
    Fixes: https://pagure.io/freeipa/issue/7548
    Signed-off-by: Christian Heimes <cheimes@redhat.com>
    Reviewed-By: Fraser Tweedale <ftweedal@redhat.com>