helm: clean up helm hook resources

[gebinic]

What type of PR is this?

• helm: clean up helm hook resources

What this PR does / why we need it:

When helm uninstall is executed, some resources of the envoy gateway remain in the k8s cluster. Some resources contain Helm hooks and are no longer managed by Helm, so they must be cleaned up manually.

Release Notes: No

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 70.75%. Comparing base (c05d438) to head (714116c).
Report is 5 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #6489      +/-   ##
==========================================
+ Coverage   70.74%   70.75%   +0.01%     
==========================================
  Files         220      220              
  Lines       37594    37594              
==========================================
+ Hits        26597    26601       +4     
+ Misses       9432     9428       -4     
  Partials     1565     1565              

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[zirain]

I didn't quite understand when will this happen?
I deploy the chart very often, I didn't notice that resources remained except CRDs.

[gebinic]

This happens because helm uninstall does not delete resources created by hooks. All resources from the certgen-rbac.yaml are created by a Helm hook and won't be deleted when helm uninstall is executed.

https://helm.sh/docs/topics/charts_hooks/#hook-resources-are-not-managed-with-corresponding-releases