$ git clone -n https://src.fedoraproject.org/rpms/kf6-kxmlgui.git /var/lib/mock/f40-build-787157-134734/root/chroot_tmpdir/scmroot/kf6-kxmlgui
Cloning into '/var/lib/mock/f40-build-787157-134734/root/chroot_tmpdir/scmroot/kf6-kxmlgui'...
$ git fetch origin 5717d696b1d5ea432095aacb4f05675eec17685e:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/kf6-kxmlgui
 * [new ref]         5717d696b1d5ea432095aacb4f05675eec17685e -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 5717d69 6.0.0