Bump php-stubs/wordpress-stubs from 6.3.0 to 6.4.1 (#422)

Bumps [php-stubs/wordpress-stubs](https://github.com/php-stubs/wordpress-stubs) from 6.3.0 to 6.4.1.
- [Release notes](https://github.com/php-stubs/wordpress-stubs/releases)
- [Commits](php-stubs/wordpress-stubs@v6.3.0...v6.4.1)

---
updated-dependencies:
- dependency-name: php-stubs/wordpress-stubs
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>