Migrate to structured logging (klog)

[aledbf]

What this PR does / why we need it:

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Which issue/s this PR fixes

How Has This Been Tested?

Checklist:

• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I've read the CONTRIBUTION guide
• I have added tests to cover my changes.
• All new and existing tests passed.

[aledbf]

/hold

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: aledbf

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• OWNERS [aledbf]

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[codecov-commenter]

Codecov Report

Merging #6211 into master will decrease coverage by 1.90%.
The diff coverage is 52.30%.

@@            Coverage Diff             @@
##           master    #6211      +/-   ##
==========================================
- Coverage   58.71%   56.80%   -1.91%     
==========================================
  Files          88       88              
  Lines        6966     6295     -671     
==========================================
- Hits         4090     3576     -514     
+ Misses       2427     2278     -149     
+ Partials      449      441       -8     

Impacted Files	Coverage Δ
...ternal/ingress/annotations/backendprotocol/main.go	100.00% <ø> (ø)
internal/ingress/annotations/parser/main.go	73.33% <ø> (-2.01%)	⬇️
internal/ingress/annotations/rewrite/main.go	48.78% <ø> (-1.22%)	⬇️
...ternal/ingress/annotations/sessionaffinity/main.go	57.77% <ø> (-2.64%)	⬇️
internal/ingress/controller/endpoints.go	92.68% <ø> (-0.66%)	⬇️
internal/ingress/controller/nginx.go	29.04% <0.00%> (-1.06%)	⬇️
internal/ingress/controller/process/nginx.go	100.00% <ø> (ø)
internal/ingress/controller/status.go	0.00% <ø> (ø)
internal/ingress/controller/store/backend_ssl.go	40.42% <ø> (-2.44%)	⬇️
internal/ingress/controller/tcp.go	0.00% <0.00%> (ø)
... and 112 more

---

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[aledbf]

/hold cancel

[aledbf]

/retest

[aledbf]

/retest