Bump phpunit/phpunit from 11.2.8 to 11.3.0 in /examples/php-phpunit

Bumps [phpunit/phpunit](https://github.com/sebastianbergmann/phpunit) from 11.2.8 to 11.3.0.
- [Release notes](https://github.com/sebastianbergmann/phpunit/releases)
- [Changelog](https://github.com/sebastianbergmann/phpunit/blob/11.3.0/ChangeLog-11.3.md)
- [Commits](sebastianbergmann/phpunit@11.2.8...11.3.0)

---
updated-dependencies:
- dependency-name: phpunit/phpunit
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

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