Add flag to allow custom ingress status update intervals

[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

fixes #5049

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.

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: aledbf

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Needs approval from an approver in each of these files:

• OWNERS [aledbf]

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[codecov-io]

Codecov Report

❗ No coverage uploaded for pull request base (master@76077ac). Click here to learn what that means.
The diff coverage is 66.66%.

@@            Coverage Diff            @@
##             master    #5050   +/-   ##
=========================================
  Coverage          ?   58.58%           
=========================================
  Files             ?       88           
  Lines             ?     6847           
  Branches          ?        0           
=========================================
  Hits              ?     4011           
  Misses            ?     2400           
  Partials          ?      436

Impacted Files	Coverage Δ
internal/ingress/status/status.go	70.98% <0%> (ø)
cmd/nginx/flags.go	84.02% <100%> (ø)

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