docs(contributing): detail how to test a PR

[mloiseleur]

Description

It explains to users how to test a PR.

Checklist

• Unit tests updated
• End user documentation updated

[ivankatliarchuk]

lgtm

[ivankatliarchuk]

There is as well this document https://github.com/kubernetes-sigs/external-dns/blob/master/docs/contributing/dev-guide.md

Maybe we need to add this links to pull request template ? https://github.com/kubernetes-sigs/external-dns/blob/master/.github/pull_request_template.md

[mloiseleur]

There is as well this document https://github.com/kubernetes-sigs/external-dns/blob/master/docs/contributing/dev-guide.md

It's more for users than for developers. The contributing section in readme references both, so I think we're good.

Maybe we need to add this links to pull request template ? https://github.com/kubernetes-sigs/external-dns/blob/master/.github/pull_request_template.md

I'm not sure 🤔. I'll open an other PR to update it, let's see if we can insert it in a convenient way.

/approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: ivankatliarchuk, mloiseleur

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