$ git clone -n https://src.fedoraproject.org/rpms/plasma-discover.git /var/lib/mock/f42-build-side-1-3579089-46814/root/chroot_tmpdir/scmroot/plasma-discover
Cloning into '/var/lib/mock/f42-build-side-1-3579089-46814/root/chroot_tmpdir/scmroot/plasma-discover'...
$ git fetch origin 2932335cf46b5c3864a91a8b8be3076b697dfbc1:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/plasma-discover
 * [new ref]         2932335cf46b5c3864a91a8b8be3076b697dfbc1 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 2932335 6.4.1