$ git clone -n https://src.fedoraproject.org/rpms/libre.git /var/lib/mock/f42-build-534-74/root/chroot_tmpdir/scmroot/libre
Cloning into '/var/lib/mock/f42-build-534-74/root/chroot_tmpdir/scmroot/libre'...
$ git fetch origin 958818e2cb382b9926d06bf13c16433fda01ff40:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/libre
 * [new ref]         958818e2cb382b9926d06bf13c16433fda01ff40 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 958818e Upgrade to 3.23.0 (#2370224)