$ git clone -n https://src.fedoraproject.org/rpms/plasma-discover.git /var/lib/mock/f42-build-side-1-3554994-46650/root/chroot_tmpdir/scmroot/plasma-discover
Cloning into '/var/lib/mock/f42-build-side-1-3554994-46650/root/chroot_tmpdir/scmroot/plasma-discover'...
$ git fetch origin 31afd2bb1f51fae36675605b8f0aa24a17af94cd:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/plasma-discover
 * [new ref]         31afd2bb1f51fae36675605b8f0aa24a17af94cd -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 31afd2b 6.4.0