Prometheus server should use SA token when talking to apiserver

[mengqiy]

What type of PR is this?

/kind bug

What this PR does / why we need it:

Prometheus server should use service account token when talking to kube-apiserver. We should not rely on anonymous auth.

Which issue(s) this PR fixes:

Fixes #

Special notes for your reviewer:

We currently create ClusterRole and ClusterRoleBinding for anonymous auth.

perf-tests/clusterloader2/pkg/prometheus/prometheus.go

Lines 370 to 388 in 6b7d01a

	createClusterRole := func() error {
	_, err := clientSet.GetClient().RbacV1().ClusterRoles().Create(context.TODO(), &rbacv1.ClusterRole{
	ObjectMeta: metav1.ObjectMeta{Name: "apiserver-metrics-viewer"},
	Rules: []rbacv1.PolicyRule{
	{Verbs: []string{"get"}, NonResourceURLs: []string{"/metrics"}},
	},
	}, metav1.CreateOptions{})
	return err
	}
	createClusterRoleBinding := func() error {
	_, err := clientSet.GetClient().RbacV1().ClusterRoleBindings().Create(context.TODO(), &rbacv1.ClusterRoleBinding{
	ObjectMeta: metav1.ObjectMeta{Name: "system:anonymous"},
	RoleRef: rbacv1.RoleRef{Kind: "ClusterRole", Name: "apiserver-metrics-viewer"},
	Subjects: []rbacv1.Subject{
	{Kind: "User", Name: "system:anonymous"},
	},
	}, metav1.CreateOptions{})
	return err
	}

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by: mengqiy
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[mengqiy]

/retest

[k8s-ci-robot]

@mengqiy: The following test failed, say /retest to rerun all failed tests or /retest-required to rerun all mandatory failed tests:

Test name	Commit	Details	Required	Rerun command
pull-perf-tests-clusterloader2-kubemark	598e901	link	true	/test pull-perf-tests-clusterloader2-kubemark

Full PR test history. Your PR dashboard. Please help us cut down on flakes by linking to an open issue when you hit one in your PR.

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