$ git clone -n https://src.fedoraproject.org/rpms/perl-String-Random.git /var/lib/mock/f45-build-26382-617/root/chroot_tmpdir/scmroot/perl-String-Random
Cloning into '/var/lib/mock/f45-build-26382-617/root/chroot_tmpdir/scmroot/perl-String-Random'...
$ git fetch origin 9a190f6af7667198dfb0ea2edc92c921f7516af4:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-String-Random
 * [new ref]         9a190f6af7667198dfb0ea2edc92c921f7516af4 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 9a190f6 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild