*: remove nikhiljindal from OWNERS

cmd/kube-apiserver/OWNERS

@@ -6,7 +6,6 @@ approvers:
 - lavalamp
 - liggitt
 - mml
-- nikhiljindal
 - smarterclayton
 - sttts
 reviewers:
@@ -19,7 +18,6 @@ reviewers:
 - caesarxuchao
 - mikedanese
 - liggitt
-- nikhiljindal
 - ncdc
 - sttts
 - hzxuzhonghu
@@ -28,3 +26,6 @@ reviewers:
 labels:
 - sig/api-machinery
 - area/apiserver
+
+emeritus_approvers:
+- nikhiljindal