feat(azure): add zone name filter for Azure Private DNS

[khuedoan]

Description

This patch implements the --zone-name-filter flag for Azure Private DNS, similar to its current implementation in Azure (public) DNS.

The behavior is the same: when used, the --domain-filter flag filters Ingress domains, not Azure Private DNS zone name.

Use case:

• We have multiple clusters using the same Azure Private DNS zone
• We want to ensure that each cluster can only modify records with its name as the prefix, for example:
  • The dev cluster can only modify argocd.dev.private.example.com (and other *.dev records)
  • The staging cluster can only modify argocd.staging.private.example.com(and other *.staging records)
  • The dev cluster cannot modify argocd.staging.private.example.com

Related PR that implemented the same feature for Azure (public) DNS: #1060

Fixes: there's no issue for this yet (but I'm happy to create one if needed).

Checklist

• Unit tests updated
• End user documentation updated

[linux-foundation-easycla]

The committers listed above are authorized under a signed CLA.

• ✅ login: khuedoan / name: Khue Doan (425dea4, aa396a9, 3852a36, 2cad978, b16d1b3)

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[mloiseleur]

Hello @khuedoan ,

Thanks for this well written PR. Changing one parameter behavior when a second one is set becomes often a bad UserXP.
I'm not sure to understand why you need it that way.

Would you please detail your use case in an issue, with (at least one) example ?

[khuedoan]

Hi @mloiseleur, thank you so much for reviewing! I created an issue #4372 with details about our setup and use case.

I also feel like it's not good a UX if one flag changes the behavior of another, but if I understand correctly, --zone-name-filter was added in #1060 for backward compatibility reasons? 🤔

[szuecs]

/ok-to-test
/approve

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[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: szuecs

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[mloiseleur]

/lgtm