Add mgmt configmap tests

[nginx-bot]

Proposed changes

• Adding mgmt configmap tests
• Fix bug: at runtime a mgmt ClientAuth cert was in the wrong directory.

Checklist

Before creating a PR, run through this checklist and mark each as complete.

• I have read the CONTRIBUTING doc
• I have added tests that prove my fix is effective or that my feature works
• I have checked that all unit tests pass after adding my changes
• I have updated necessary documentation
• I have rebased my branch onto main
• I will ensure my PR is targeting the main branch and pulling from my branch from my own fork

[codecov]

Codecov Report

Attention: Patch coverage is 28.57143% with 25 lines in your changes missing coverage. Please review.

Project coverage is 52.54%. Comparing base (025ddd7) to head (60d540b).

Files with missing lines	Patch %	Lines
internal/k8s/controller.go	0.00%	21 Missing ⚠️
internal/configs/configurator.go	71.42%	4 Missing ⚠️

Additional details and impacted files

@@               Coverage Diff               @@
##           release-4.0    #6965      +/-   ##
===============================================
- Coverage        52.59%   52.54%   -0.05%     
===============================================
  Files               88       88              
  Lines            20789    20803      +14     
===============================================
- Hits             10933    10931       -2     
- Misses            9401     9417      +16     
  Partials           455      455              

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