$ git clone -n https://src.fedoraproject.org/rpms/kf6-kiconthemes.git /var/lib/mock/f42-build-side-1-3576644-46805/root/chroot_tmpdir/scmroot/kf6-kiconthemes
Cloning into '/var/lib/mock/f42-build-side-1-3576644-46805/root/chroot_tmpdir/scmroot/kf6-kiconthemes'...
$ git fetch origin 6b1f3cc305f5b592e94b3f4175b4065f994113e1:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/kf6-kiconthemes
 * [new ref]         6b1f3cc305f5b592e94b3f4175b4065f994113e1 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 6b1f3cc 6.15 and plasma 3.4 compatibility rebuild