$ git clone -n https://src.fedoraproject.org/rpms/libdex.git /var/lib/mock/f40-build-785580-134021/root/chroot_tmpdir/scmroot/libdex
Cloning into '/var/lib/mock/f40-build-785580-134021/root/chroot_tmpdir/scmroot/libdex'...
$ git fetch origin e98754f5cbd405c9011a73d3542280d6f175dae6:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/libdex
 * [new ref]         e98754f5cbd405c9011a73d3542280d6f175dae6 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at e98754f Update to 0.5.0 (#2263919)