$ git clone -n https://src.fedoraproject.org/rpms/rubygem-zeitwerk.git /var/lib/mock/f45-build-35471-695/root/chroot_tmpdir/scmroot/rubygem-zeitwerk
Cloning into '/var/lib/mock/f45-build-35471-695/root/chroot_tmpdir/scmroot/rubygem-zeitwerk'...
$ git fetch origin 13d5f8b1c915d095f911725fb0678e817967e3d0:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rubygem-zeitwerk
 * [new ref]         13d5f8b1c915d095f911725fb0678e817967e3d0 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 13d5f8b Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild