$ git clone -n https://src.fedoraproject.org/rpms/cups-pk-helper.git /var/lib/mock/f45-build-5488-339/root/chroot_tmpdir/scmroot/cups-pk-helper
Cloning into '/var/lib/mock/f45-build-5488-339/root/chroot_tmpdir/scmroot/cups-pk-helper'...
$ git fetch origin 68d894ab19341c335d667e0ff926096252bef23b:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/cups-pk-helper
 * [new ref]         68d894ab19341c335d667e0ff926096252bef23b -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 68d894a Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild