$ git clone -n https://src.fedoraproject.org/rpms/rubygem-sshkey.git /var/lib/mock/f45-build-35332-694/root/chroot_tmpdir/scmroot/rubygem-sshkey
Cloning into '/var/lib/mock/f45-build-35332-694/root/chroot_tmpdir/scmroot/rubygem-sshkey'...
$ git fetch origin d56e06cfa9e2a42862bf420cddd31e5dd5400476:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rubygem-sshkey
 * [new ref]         d56e06cfa9e2a42862bf420cddd31e5dd5400476 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at d56e06c Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild