Add zone-sync ConfigMap Keys to docs

[AlexFenlon]

Proposed changes

• Add doc changes to configmap keys for Add zone-sync with no TLS to ConfigMap #7347
• Add notice to let users that previously used snippets to remove it before enabling. the new zone-sync
• updated a mention of zone-sync in OIDC docs to reflect these changes

Resolves: #7277

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

[github-actions]

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[javorszky]

Do these new options have default values? If I don't set a zone-sync-resolver-valid option, what's the TTL going to be?

What's the default for the ipv6?

[AlexFenlon]

Do these new options have default values? If I don't set a zone-sync-resolver-valid option, what's the TTL going to be?

What's the default for the ipv6?

@javorszky

Yes, these new options have default values, IF zone-sync is set and only if zone-sync is set.
If you try to enable zone-sync-resolver-valid for example, it will tell you to enable zone-sync first.

the default for IPV6 on/true as it is it also nginx's default here.

the default config is below if the user has zone-sync: "true" and is using a deployment (replicaset)

 server { listen 12345; listen [::]:12345; resolver kube-dns.kube-system.svc.cluster.local valid=5s; zone_sync; zone_sync_server nginx-ingress-replicaset-headless.nginx-ingress-replicaset.svc.cluster.local:12345 resolve; } 

[jjngx]

🚀

[ADubhlaoich]

Generally LGTM but please look at my edit suggestions.