$ git clone -n https://src.fedoraproject.org/rpms/lxsession.git /var/lib/mock/f42-build-side-1-3500620-45970/root/chroot_tmpdir/scmroot/lxsession
Cloning into '/var/lib/mock/f42-build-side-1-3500620-45970/root/chroot_tmpdir/scmroot/lxsession'...
$ git fetch origin 1a5fceb139f1575a8b003e6e4c7b62ebbf328b90:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/lxsession
 * [new ref]         1a5fceb139f1575a8b003e6e4c7b62ebbf328b90 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 1a5fceb 0.5.6