$ git clone -n https://src.fedoraproject.org/rpms/box64.git /var/lib/mock/f38-build-side-42-init-devel-1412054-31434/root/chroot_tmpdir/scmroot/box64
Cloning into '/var/lib/mock/f38-build-side-42-init-devel-1412054-31434/root/chroot_tmpdir/scmroot/box64'...
$ git fetch origin cc7636b870b9027048857da6b3ad0005e87ce733:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/box64
 * [new ref]         cc7636b870b9027048857da6b3ad0005e87ce733 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at cc7636b Update to 0.2.4