proxy: followup to last-queued-change metric

Fixes two small issues with the metric added in #90175:

1. Bump the timestamp on initial informer sync. Otherwise it remains 0 if
   restarting kube-proxy in a quiescent cluster, which isn't quite right.
2. Bump the timestamp even if no healthz server is specified.

pkg/proxy/winkernel/proxier.go

@@ -34,7 +34,7 @@ import (
 	"github.com/davecgh/go-spew/spew"
 	"k8s.io/klog"
 
-	"k8s.io/api/core/v1"
+	v1 "k8s.io/api/core/v1"
 	"k8s.io/apimachinery/pkg/types"
 	"k8s.io/apimachinery/pkg/util/intstr"
 	"k8s.io/apimachinery/pkg/util/sets"
@@ -736,8 +736,8 @@ func getHnsNetworkInfo(hnsNetworkName string) (*hnsNetworkInfo, error) {
 func (proxier *Proxier) Sync() {
 	if proxier.healthzServer != nil {
 		proxier.healthzServer.QueuedUpdate()
-		metrics.SyncProxyRulesLastQueuedTimestamp.SetToCurrentTime()
 	}
+	metrics.SyncProxyRulesLastQueuedTimestamp.SetToCurrentTime()
 	proxier.syncRunner.Run()
 }
 
@@ -747,6 +747,8 @@ func (proxier *Proxier) SyncLoop() {
 	if proxier.healthzServer != nil {
 		proxier.healthzServer.Updated()
 	}
+	// synthesize "last change queued" time as the informers are syncing.
+	metrics.SyncProxyRulesLastQueuedTimestamp.SetToCurrentTime()
 	proxier.syncRunner.Loop(wait.NeverStop)
 }