$ git clone -n https://src.fedoraproject.org/rpms/libdex.git /var/lib/mock/f40-build-2247035-53842/root/chroot_tmpdir/scmroot/libdex
Cloning into '/var/lib/mock/f40-build-2247035-53842/root/chroot_tmpdir/scmroot/libdex'...
$ git fetch origin 9ccec5ae43bd8c04792f894fb96ba545cbdaf3e1:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/libdex
 * [new ref]         9ccec5ae43bd8c04792f894fb96ba545cbdaf3e1 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 9ccec5a Update to 0.4.3