feat(admission controller): add ValidatingWebhookConfigurations RBAC

[wdhif]

What does this PR do?

Adds the necessary RBACs for the Cluster Agent to modify the ValidatingWebhookConfigurations.

Motivation

This is needed to support the new ValidatingAdmissionWebhook controller in the Agent's Admission Controller.

Minimum Agent Versions

Agent: v7.58.0
Cluster Agent: v7.58.0

Describe your test plan

Build the Operator and validate that the new ValidatingAdmissionWebhook is created with the new Agent.

➜ k describe validatingwebhookconfigurations.admissionregistration.k8s.io datadog-webhook
Name:         datadog-webhook
Namespace:
Labels:       <none>
Annotations:  <none>
API Version:  admissionregistration.k8s.io/v1
Kind:         ValidatingWebhookConfiguration
Metadata:
  Creation Timestamp:  2024-08-28T09:07:22Z
  Generation:          1
  Resource Version:    832
  UID:                 efd5e35d-8257-46ba-bdc7-b35268bf7c15
Events:                <none>

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 23.52941% with 13 lines in your changes missing coverage. Please review.

Project coverage is 47.11%. Comparing base (ddaac56) to head (6cab9e8).

Files with missing lines	Patch %	Lines
pkg/equality/equality.go	0.00%	9 Missing ⚠️
pkg/kubernetes/objects.go	0.00%	2 Missing ⚠️
pkg/kubernetes/objectslist.go	0.00%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1377      +/-   ##
==========================================
- Coverage   47.14%   47.11%   -0.03%     
==========================================
  Files         217      217              
  Lines       18768    18782      +14     
==========================================
+ Hits         8849     8850       +1     
- Misses       9457     9470      +13     
  Partials      462      462              

Flag	Coverage Δ
unittests	47.11% <23.52%> (-0.03%)	⬇️

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

Files with missing lines	Coverage Δ
...s/datadogagent/feature/admissioncontroller/rbac.go	89.65% <100.00%> (ø)
controllers/datadogagent_controller.go	70.00% <ø> (ø)
pkg/kubernetes/const.go	87.50% <100.00%> (+0.54%)	⬆️
pkg/kubernetes/objects.go	0.00% <0.00%> (ø)
pkg/kubernetes/objectslist.go	0.00% <0.00%> (ø)
pkg/equality/equality.go	11.62% <0.00%> (-0.65%)	⬇️

---

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 ddaac56...6cab9e8. Read the comment docs.