refactor: replace glog in externaldns & certmanager

[pdabelf5]

Proposed changes

Replace glog with slog in certmanager & externaldns packages for:

• certmanager/cm_controller.go
• certmanager/sync.go
• externaldns/controller.go
• externaldns/sync.go

NOTE:

GLog Levels	Slog Levels
glog.V(3).Infof()	log.Debugf()
glog.V(3).Info()	log.Debug()
glog.V(2).Infof()	log.Debugf()
glog.V(2).Info()	log.Debugf()
glog.Infof()	log.Infof()
glog.Info()	log.Info()
glog.Warningf()	log.Warnf()
glog.Warning()	log.Warn()
glog.Errorf()	log.Errorf()
glog.Error()	log.Error()
glog.Fatalf()	log.Fatalf()
glog.Fatal()	log.Fatal()

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 30.88235% with 47 lines in your changes missing coverage. Please review.

Project coverage is 53.15%. Comparing base (89dbaa6) to head (a99302f).
Report is 4 commits behind head on main.

Files with missing lines	Patch %	Lines
internal/certmanager/cm_controller.go	0.00%	16 Missing ⚠️
internal/externaldns/controller.go	0.00%	16 Missing ⚠️
internal/externaldns/sync.go	59.09%	9 Missing ⚠️
internal/certmanager/sync.go	66.66%	4 Missing ⚠️
internal/k8s/controller.go	0.00%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #6586      +/-   ##
==========================================
+ Coverage   53.07%   53.15%   +0.08%     
==========================================
  Files          87       87              
  Lines       16218    16235      +17     
==========================================
+ Hits         8607     8630      +23     
+ Misses       7203     7191      -12     
- Partials      408      414       +6     

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