Tolerate unready endpoints for apiserver service

This avoids a race condition that can occur while joining nodes when
another node is down.

The service is really a discovery service that is primarily used by the
haproxy chart to find apiserver endpoints, so it's reasonable for it to
include all endpoints (HAProxy will monitor health on its own).

Change-Id: I09dd66883af4ff91f9d13432137094fdf876ca83

charts/apiserver/templates/service.yaml

@@ -21,6 +21,8 @@ apiVersion: v1
 kind: Service
 metadata:
   name: {{ .Values.service.name }}
+  annotations:
+    service.alpha.kubernetes.io/tolerate-unready-endpoints: "true"
 spec:
   ports:
     {{ if .Values.network.kubernetes_apiserver.enable_node_port }}