$ git clone -n https://src.fedoraproject.org/rpms/octave-gsl.git /var/lib/mock/f41-build-side-1-2969457-35819/root/chroot_tmpdir/scmroot/octave-gsl
Cloning into '/var/lib/mock/f41-build-side-1-2969457-35819/root/chroot_tmpdir/scmroot/octave-gsl'...
$ git fetch origin d0caa21f53778aa7f1a4cb5c986fe820a6807505:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/octave-gsl
 * [new ref]         d0caa21f53778aa7f1a4cb5c986fe820a6807505 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at d0caa21 convert GPLv2+ license to SPDX