$ git clone -n https://git.cclinux.org/stage/rpms/iperf3.git /var/lib/mock/dist-circle9-build-124116-87973/root/chroot_tmpdir/scmroot/iperf3
Cloning into '/var/lib/mock/dist-circle9-build-124116-87973/root/chroot_tmpdir/scmroot/iperf3'...
$ git fetch origin b14da1608d50f1403d518ed139fca22b73902dae:KOJI_FETCH_HEAD
From https://git.cclinux.org/stage/rpms/iperf3
 * [new ref]         b14da1608d50f1403d518ed139fca22b73902dae -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at b14da16 import iperf3-3.9-13.el9