chore(ci): rework labels in OWNERS

[mloiseleur]

What does it do ?

Tries to use label automation feature on OWNERS file.
It seems that current implementation has never worked.
In owners doc, it says on filters it's incompatible with labels use.
On test-infra, it's using only labels (for instance, here)

So, in this PR it:

• removes entire filters section
• tries to add a few OWNERS file setting labels

Motivation

Easier PR review / triage.

More

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

[ivankatliarchuk]

/lgtm

[mloiseleur]

/approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

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

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• OWNERS [mloiseleur]

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