sample controller: enhance context support

27a68ae introduced context support for events. Creating an event
broadcaster with context makes tests more resilient against leaking goroutines
when that context gets canceled at the end of a test and enables per-test
output via ktesting.

The New method already had a context, therefore no API changes are needed.

staging/src/k8s.io/sample-controller/controller.go

@@ -101,7 +101,7 @@ func NewController(
 	utilruntime.Must(samplescheme.AddToScheme(scheme.Scheme))
 	logger.V(4).Info("Creating event broadcaster")
 
-	eventBroadcaster := record.NewBroadcaster()
+	eventBroadcaster := record.NewBroadcaster(record.WithContext(ctx))
 	eventBroadcaster.StartStructuredLogging(0)
 	eventBroadcaster.StartRecordingToSink(&typedcorev1.EventSinkImpl{Interface: kubeclientset.CoreV1().Events("")})
 	recorder := eventBroadcaster.NewRecorder(scheme.Scheme, corev1.EventSource{Component: controllerAgentName})