Update code owners

[nacx]

Update the code owners to the current active people, so that code reviews can happen in a timely manner.

It mgirates from the OWNERS file to GitHub CODEOWNERS. Once this is merged, a follow-up change will be done in istio/test-infra to update the Ci requirements accordingly.

@BrenoDeMedeiros @liminw @lizan @sawlanipradeep @incfly @Shikugawa you were listed in the OWNERS file, but as far as I know you're not active anymore in the project. Please leave a comment if you want to be kept in the CODEOWNERS file and I would be happy to add you before merging the PR. Thank you! :)

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

:exclamation: No coverage uploaded for pull request base (main@11a2002). Click here to learn what that means.

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Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #248 +/- ## ======================================= Coverage ? 90.31% ======================================= Files ? 24 Lines ? 1569 Branches ? 0 ======================================= Hits ? 1417 Misses ? 108 Partials ? 44 ```

[nacx]

/hold

[istio-testing]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: nacx, Shikugawa

The full list of commands accepted by this bot can be found here.

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Needs approval from an approver in each of these files: - ~~[OWNERS](https://github.com/istio-ecosystem/authservice/blob/main/OWNERS)~~ [Shikugawa,nacx] Approvers can indicate their approval by writing `/approve` in a comment Approvers can cancel approval by writing `/approve cancel` in a comment

[incfly]

/lgtm.

[nacx]

/unhold

[nacx]

It's been 1 week and there were no objections, so let's have this merged. We can always add back any maintainer that wants to be a code owner.