Fix ports collision when hostNetwork=true

[aledbf]

What this PR does / why we need it:

The ports for the lua configuration of HTTP and TCP/UDP should not use ports already defined in Kubernetes. This PR also introduces two flags to allow different port values.

Which issue this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close that issue when PR gets merged): fixes #4616

Special notes for your reviewer:

[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-io]

Codecov Report

❗ No coverage uploaded for pull request base (master@9ecec0d). Click here to learn what that means.
The diff coverage is 47.05%.

@@            Coverage Diff            @@
##             master    #4617   +/-   ##
=========================================
  Coverage          ?   58.68%           
=========================================
  Files             ?       88           
  Lines             ?     6763           
  Branches          ?        0           
=========================================
  Hits              ?     3969           
  Misses            ?     2355           
  Partials          ?      439

Impacted Files	Coverage Δ
cmd/nginx/main.go	6.53% <0%> (ø)
internal/ingress/controller/controller.go	50.55% <0%> (ø)
cmd/nginx/flags.go	86.66% <57.14%> (ø)

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