ci: ignore go.sum from codespell check
ci: ignore go.sum from codespell check

as go-sum is auto generated, ignore checking
codespell on this file.

Signed-off-by: Madhu Rajanna <60fbf37a92c2a0908e31296d18dadbec5a4dae17@gmail.com>

ceph/ceph-csi,ceph/ceph-csi,ceph/ceph-csi,ceph/ceph-csi