$ git clone -n https://src.fedoraproject.org/rpms/filezilla.git /var/lib/mock/f42-build-side-1-3511139-46047/root/chroot_tmpdir/scmroot/filezilla
Cloning into '/var/lib/mock/f42-build-side-1-3511139-46047/root/chroot_tmpdir/scmroot/filezilla'...
$ git fetch origin b4fd35a332eae8e599ee63e4b58c8075939de7a8:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/filezilla
 * [new ref]         b4fd35a332eae8e599ee63e4b58c8075939de7a8 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at b4fd35a 3.69.0