$ git clone -n https://src.fedoraproject.org/rpms/f3.git /var/lib/mock/f45-build-8591-391/root/chroot_tmpdir/scmroot/f3
Cloning into '/var/lib/mock/f45-build-8591-391/root/chroot_tmpdir/scmroot/f3'...
$ git fetch origin b0c0810213c8ceab857176a49b6d961de1e9b329:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/f3
 * [new ref]         b0c0810213c8ceab857176a49b6d961de1e9b329 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at b0c0810 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild