Title: #806: sudo: always use server highest usn for smart refresh
It's not clear to me whether you want to cherry-pick the patches to the stable branch
or not..if yes, just please tell me.
(I was about to push the patches to sssd-1-16 as well, btu wasn't sure if this is more
of a straight bug fix or a change of behaviour, even if the correct change)
See the full comment at https://github.com/SSSD/sssd/pull/806#issuecomment-494538048