Handle vendor change in k8s.io/apimachinery/pkg/util/clock

clock.Clock used to have Tick() method, but is now replaced with
NewTicker() method to prevent leaking. Changed NPD code to adapt to it.

See https://github.com/kubernetes/apimachinery/commit/10ebc22e for more
detail.

pkg/exporters/k8sexporter/condition/manager.go

@@ -110,10 +110,11 @@ func (c *conditionManager) GetConditions() []types.Condition {
 }
 
 func (c *conditionManager) syncLoop() {
-	updateCh := c.clock.Tick(updatePeriod)
+	ticker := c.clock.NewTicker(updatePeriod)
+	defer ticker.Stop()
 	for {
 		select {
-		case <-updateCh:
+		case <-ticker.C():
 			if c.needUpdates() || c.needResync() || c.needHeartbeat() {
 				c.sync()
 			}