Update to shibboleth-sp RPMs

[Cantor, Scott]

A new package revision, 2.5.5-3.1, will be appearing on the mirrors shortly, to correct a /var/run-handling bug affecting successful shibd startup after a reboot [1] on systemd platforms.

The package update should correct that problem. No other changes were made. While the update doesn't really do anything on older systems, I prefer to keep the packages in sync for obvious reasons.

-- Scott

[1] https://issues.shibboleth.net/jira/browse/SSPCPP-665