$ git clone -n https://src.fedoraproject.org/rpms/filesystem.git /var/lib/mock/f41-build-side-1-2818866-33043/root/chroot_tmpdir/scmroot/filesystem
Cloning into '/var/lib/mock/f41-build-side-1-2818866-33043/root/chroot_tmpdir/scmroot/filesystem'...
$ git fetch origin d5a963934afc40156c82bc61f34ac1b6ff24487d:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/filesystem
 * [new ref]         d5a963934afc40156c82bc61f34ac1b6ff24487d -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at d5a9639 Add ownership of /etc/default