$ git clone -n https://src.fedoraproject.org/rpms/airrac.git /var/lib/mock/f42-build-885487-186795/root/chroot_tmpdir/scmroot/airrac
Cloning into '/var/lib/mock/f42-build-885487-186795/root/chroot_tmpdir/scmroot/airrac'...
$ git fetch origin 3e2025164d54fd77afaddb7b9484df69ecef6cbb:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/airrac
 * [new ref]         3e2025164d54fd77afaddb7b9484df69ecef6cbb -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 3e20251 Upstream update