$ git clone -n https://src.fedoraproject.org/rpms/qjson.git /var/lib/mock/f41-build-1032089-18543/root/chroot_tmpdir/scmroot/qjson
Cloning into '/var/lib/mock/f41-build-1032089-18543/root/chroot_tmpdir/scmroot/qjson'...
$ git fetch origin b856640523384e86ce3961f8e51fb864e1f24149:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/qjson
 * [new ref]         b856640523384e86ce3961f8e51fb864e1f24149 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at b856640 Eliminate use of obsolete %patchN syntax (#2283636)