chore(provider/coredns): improve code coverage and reduce complexity

[ivankatliarchuk]

What does it do ?

Improves code coverage for provider coredns, and reduce code complexity for certain functions

Motivation

• Help required to reduce cyclomatic complexity of the code #5419
• external-dns improve code coverage #5150

Complexity from 27 to 10

Before 66% coverage

After 92% coverage

More

• Yes, this PR title follows Conventional Commits
• Yes, I added unit tests
• Yes, I updated end user documentation accordingly

[mloiseleur]

@linoleparquet @upsaurav12 Do you think you can review this PR ?

[upsaurav12]

@linoleparquet @upsaurav12 Do you think you can review this PR ?

Sure !

[linolayani]

looking good to me 👍

[k8s-ci-robot]

@linoleparquet: changing LGTM is restricted to collaborators

Details

In response to this:

looking good to me 👍

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[ivankatliarchuk]

@mloiseleur wdyt ok to be merged?

[upsaurav12]

looking good to me 👍

[mloiseleur]

/lgtm
/approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

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

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• provider/coredns/OWNERS [mloiseleur]

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[mloiseleur]

Thanks @upsaurav12 and @linoleparquet