$ git clone -n https://src.fedoraproject.org/rpms/trademgen.git /var/lib/mock/f42-build-3531211-46322/root/chroot_tmpdir/scmroot/trademgen
Cloning into '/var/lib/mock/f42-build-3531211-46322/root/chroot_tmpdir/scmroot/trademgen'...
$ git fetch origin 3fbd0da32745a2866399fbbe9f454102e08bff89:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/trademgen
 * [new ref]         3fbd0da32745a2866399fbbe9f454102e08bff89 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 3fbd0da Upstream upgrade