$ git clone -n https://src.fedoraproject.org/rpms/octave-symbolic.git /var/lib/mock/f39-build-1681006-41025/root/chroot_tmpdir/scmroot/octave-symbolic
Cloning into '/var/lib/mock/f39-build-1681006-41025/root/chroot_tmpdir/scmroot/octave-symbolic'...
$ git fetch origin 969c64da2d3ba90211ceb755883b05463e855125:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/octave-symbolic
 * [new ref]         969c64da2d3ba90211ceb755883b05463e855125 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 969c64d Depend on python3-packaging, should be FTBFS