fix(Google DNS): ensure trailing dot on NS records

[abaguas]

Description

NS records added in Google Cloud DNS must have a trailing dot. Otherwise the API throws the following error:

time="2024-11-04T10:34:20Z" level=error msg="googleapi: Error 400: Invalid value for 'entity.change.additions[cloud.k8gb.io.][NS].rrdata[0]': 'gslb-ns-eu-cloud.k8gb.io', invalid"

This is similar to CNAME, MX and SRV records.

---

This change was tested with the a DNSEndpoint CRD containing the following endpoints:

    endpoints:
    - dnsName: cloud.k8gb.io
      recordTTL: 5
      recordType: NS
      targets:
      - gslb-ns-eu-cloud.k8gb.io
      - gslb-ns-us-cloud.k8gb.io
    - dnsName: gslb-ns-eu-cloud.k8gb.io

And the record was successfully created

gcloud dns record-sets list --zone="k8gb" --type=NS --name "cloud.k8gb.io."
NAME            TYPE  TTL  DATA
cloud.k8gb.io.  NS    5    gslb-ns-eu-cloud.k8gb.io.,gslb-ns-us-cloud.k8gb.io.

Checklist

• [x] Unit tests updated
• [x] End user documentation updated

[k8s-ci-robot]

Hi @abaguas. Thanks for your PR.

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[mloiseleur]

Would you please add a test for this change ?

[abaguas]

Would you please add a test for this change ?

Ups. Done @mloiseleur

[mloiseleur]

/ok-to-test

[mloiseleur]

/lgtm

[mloiseleur]

/retitle fix(Google DNS): ensure trailing dot on NS records

[Raffo]

/approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: Raffo

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