setting both of group and user in sar (#149)

Signed-off-by: Wei Liu <liuweixa@redhat.com>

Author: skeeey

pkg/cloudevents/server/grpc/authz/kube/sar.go

@@ -181,13 +181,10 @@ func toSubjectAccessReview(clusterName string, user string, groups []string, eve
 				Namespace: clusterName,
 			},
 			Groups: groups,
+			User:   user,
 		},
 	}
 
-	if len(sar.Spec.Groups) == 0 {
-		sar.Spec.User = user
-	}
-
 	if eventsType.SubResource == types.SubResourceStatus {
 		sar.Spec.ResourceAttributes.Subresource = "status"
 	}