$ git clone -n https://src.fedoraproject.org/rpms/kf6-knewstuff.git /var/lib/mock/f41-build-860298-168900/root/chroot_tmpdir/scmroot/kf6-knewstuff
Cloning into '/var/lib/mock/f41-build-860298-168900/root/chroot_tmpdir/scmroot/kf6-knewstuff'...
$ git fetch origin 3ddbf2774098edb48424068150b6eb5dbbada063:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/kf6-knewstuff
 * [new ref]         3ddbf2774098edb48424068150b6eb5dbbada063 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 3ddbf27 6.7.0