Remove kube-rbac-proxy image

[khewonc]

What does this PR do?

Removes references to image gcr.io/kubebuilder/kube-rbac-proxy

Motivation

#1545

Additional Notes

Using filters.WithAuthenticationAndAuthorization adds a dependency to k8s.io/apiserver: https://pkg.go.dev/sigs.k8s.io/controller-runtime/pkg/metrics/filters#WithAuthenticationAndAuthorization

Minimum Agent Versions

Are there minimum versions of the Datadog Agent and/or Cluster Agent required?

• Agent: vX.Y.Z
• Cluster Agent: vX.Y.Z

Describe your test plan

1. Uncomment the following in config/default/kustomization.yaml:

# [METRICS] Expose the controller manager metrics service.
- metrics_service.yaml

patches:
# [METRICS] The following patch will enable the metrics endpoint using HTTPS and the port :8443.
# More info: https://book.kubebuilder.io/reference/metrics
- path: manager_metrics_patch.yaml
  target:
   kind: Deployment

2. Uncomment the following in config/rbac/kustomization.yaml:

# The following RBAC configurations are used to protect
# the metrics endpoint with authn/authz. These configurations
# ensure that only authorized users and service accounts
# can access the metrics endpoint.
- metrics_auth_role.yaml
- metrics_auth_role_binding.yaml
- metrics_reader_role.yaml

3. Run make deploy with secureMetrics=true
4. Create a pod to curl the metrics endpoint with the proper auth:

apiVersion: v1
kind: Pod
metadata:
  name: metrics-consumer
  namespace: system
spec:
  # Use the scaffolded service account name to allow authn/authz
  serviceAccountName: datadog-operator-controller-manager
  containers:
  - name: metrics-consumer
    image: curlimages/curl:7.78.0
    command: ["/bin/sh"]
    args:
      - "-c"
      - >
        while true;
        do
          # Note here that we are passing the token obtained from the ServiceAccount to curl the metrics endpoint
          curl -v -k -H "Authorization: Bearer $(cat /var/run/secrets/kubernetes.io/serviceaccount/token)" https://datadog-operator-controller-manager-metrics-service.system.svc.cluster.local:8443/metrics;
          sleep 60;
        done

5. Check the pod logs to ensure the curl was successful (should see prometheus formatted metrics)

Checklist

• PR has at least one valid label: bug, enhancement, refactoring, documentation, tooling, and/or dependencies
• PR has a milestone or the qa/skip-qa label

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 0% with 14 lines in your changes missing coverage. Please review.

Project coverage is 48.64%. Comparing base (993280d) to head (93056db).

Files with missing lines	Patch %	Lines
cmd/main.go	0.00%	14 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1551      +/-   ##
==========================================
- Coverage   48.66%   48.64%   -0.03%     
==========================================
  Files         226      226              
  Lines       20363    20372       +9     
==========================================
  Hits         9909     9909              
- Misses       9937     9946       +9     
  Partials      517      517              

Flag	Coverage Δ
unittests	48.64% <0.00%> (-0.03%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files with missing lines	Coverage Δ
cmd/main.go	0.00% <0.00%> (ø)

---

Continue to review full report in Codecov by Sentry.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 993280d...93056db. Read the comment docs.