$ git clone -n https://src.fedoraproject.org/rpms/mac-robber.git /var/lib/mock/f45-build-17904-505/root/chroot_tmpdir/scmroot/mac-robber
Cloning into '/var/lib/mock/f45-build-17904-505/root/chroot_tmpdir/scmroot/mac-robber'...
$ git fetch origin 3c0023e604f1b0a4f888fe1111a27bef05cce512:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/mac-robber
 * [new ref]         3c0023e604f1b0a4f888fe1111a27bef05cce512 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 3c0023e Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild