$ git clone -n https://src.fedoraproject.org/rpms/vdr.git /var/lib/mock/f41-build-side-1-2771520-32235/root/chroot_tmpdir/scmroot/vdr
Cloning into '/var/lib/mock/f41-build-side-1-2771520-32235/root/chroot_tmpdir/scmroot/vdr'...
$ git fetch origin d50bb739b9d1c8ee8e656e130404883f340ec5d3:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/vdr
 * [new ref]         d50bb739b9d1c8ee8e656e130404883f340ec5d3 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at d50bb73 convert GPLv2+ license to SPDX