chore(e2e/recommender): Reuse test namespace in VPA observer controller

This commit instruments the `observer`, used within the `recommender`
e2e tests, reuse the test framework namespace. The main reason behind
this change is to allow running the test suite against an existing
cluster that already has `VPA` resources in other namespaces.

Currently, the test is considering all `namespaces` when it builds it's
`observer`'s controller, which makes the test fail when trying to validate
the recommendations for components outside of the test scope.

This behavior was discovered while running the e2e tests against a
cluster with VPA setup that uses Prometheus as history storage
provider.

Author: vitanovs

vertical-pod-autoscaler/e2e/v1/recommender.go

@@ -102,8 +102,8 @@ func (o *observer) OnUpdate(oldObj, newObj interface{}) {
 	go func() { o.channel <- result }()
 }
 
-func getVpaObserver(vpaClientSet vpa_clientset.Interface) *observer {
-	vpaListWatch := cache.NewListWatchFromClient(vpaClientSet.AutoscalingV1().RESTClient(), "verticalpodautoscalers", apiv1.NamespaceAll, fields.Everything())
+func getVpaObserver(vpaClientSet vpa_clientset.Interface, namespace string) *observer {
+	vpaListWatch := cache.NewListWatchFromClient(vpaClientSet.AutoscalingV1().RESTClient(), "verticalpodautoscalers", namespace, fields.Everything())
 	vpaObserver := observer{channel: make(chan recommendationChange)}
 	_, controller := cache.NewIndexerInformer(vpaListWatch,
 		&vpa_types.VerticalPodAutoscaler{},
@@ -232,7 +232,7 @@ var _ = RecommenderE2eDescribe("VPA CRD object", func() {
 
 	ginkgo.It("doesn't drop lower/upper after recommender's restart", func() {
 
-		o := getVpaObserver(vpaClientSet)
+		o := getVpaObserver(vpaClientSet, f.Namespace.Name)
 
 		ginkgo.By("Waiting for recommendation to be filled")
 		_, err := WaitForRecommendationPresent(vpaClientSet, vpaCRD)