Fix fedora version for xfail for sssd test
Test was failing in nightly_PR for ipa-4.7
As https://pagure.io/SSSD/sssd/issue/3978 is not available on
fedora-29
Signed-off-by: Anuja More <amore@redhat.com>
Reviewed-By: Florence Blanc-Renaud <flo@redhat.com>