$ git clone -n https://src.fedoraproject.org/rpms/kf6-kpackage.git /var/lib/mock/f42-build-side-114581-60924157-6585960/root/chroot_tmpdir/scmroot/kf6-kpackage
Cloning into '/var/lib/mock/f42-build-side-114581-60924157-6585960/root/chroot_tmpdir/scmroot/kf6-kpackage'...
$ git fetch origin f3f879274bc3d9230edd88eb7580fa828bba1cf1:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/kf6-kpackage
 * [new ref]         f3f879274bc3d9230edd88eb7580fa828bba1cf1 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at f3f8792 6.16.0