cloud-provider-vsphere: remove inactive members from OWNERS

We are cleaning up inactive members from OWNERS who haven't been active
since the release of v1.11. This commit removes luomiao from
`config/jobs/kubernetes/cloud-provider-vsphere/OWNERS`.

Author: nikhita

config/jobs/kubernetes/cloud-provider-vsphere/OWNERS

@@ -6,7 +6,6 @@ reviwers:
 - divyenpatel
 - imkin
 - kerneltime
-- luomiao
 - frapposelli
 - dougm
 - figo
@@ -18,7 +17,6 @@ approvers:
 - divyenpatel
 - imkin
 - kerneltime
-- luomiao
 - frapposelli
 - dougm
 - figo