chore: Use a team in CODEOWNERS (#2739)

## What ❔

Uses a dedicated team for release management in CODEOWNERS.

## Why ❔

Better configurability.

## Checklist

<!-- Check your PR fulfills the following items. -->
<!-- For draft PRs check the boxes as you complete them. -->

- [ ] PR title corresponds to the body of PR (we generate changelog
entries from PRs).
- [ ] Tests for the changes have been added / updated.
- [ ] Documentation comments have been added / updated.
- [ ] Code has been formatted via `zk fmt` and `zk lint`.

CODEOWNERS

@@ -1,4 +1,4 @@
-.github/release-please/** @RomanBrodetski @perekopskiy @Deniallugo @popzxc @EmilLuta
-**/CHANGELOG.md @RomanBrodetski @perekopskiy @Deniallugo @popzxc @EmilLuta
+.github/release-please/** @matter-labs/core-release-managers
+**/CHANGELOG.md @matter-labs/core-release-managers
 CODEOWNERS @RomanBrodetski @perekopskiy @Deniallugo @popzxc
 .github/workflows/** @matter-labs/devops