fix: Update MAINTAINERS.md to fix email addrsses

[StefanKurek]

Description of Changes

Please check that the PR fulfills these requirements

• [ ] Tests for the changes have been added (for bug fixes / features)
• [ ] Docs have been added / updated (for bug fixes / features)
• [ ] CI passes

[codecov[bot]]

Codecov Report

:exclamation: No coverage uploaded for pull request base (main@9a51182). Click here to learn what that means. Patch has no changes to coverable lines.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #757 +/- ## ======================================= Coverage ? 74.94% ======================================= Files ? 133 Lines ? 10095 Branches ? 0 ======================================= Hits ? 7565 Misses ? 2059 Partials ? 471 ```

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