Bump phpunit/phpunit from 12.5.7 to 12.5.8 in /api

Bumps [phpunit/phpunit](https://github.com/sebastianbergmann/phpunit) from 12.5.7 to 12.5.8.
- [Release notes](https://github.com/sebastianbergmann/phpunit/releases)
- [Changelog](https://github.com/sebastianbergmann/phpunit/blob/12.5.8/ChangeLog-12.5.md)
- [Commits](sebastianbergmann/phpunit@12.5.7...12.5.8)

---
updated-dependencies:
- dependency-name: phpunit/phpunit
  dependency-version: 12.5.8
  dependency-type: direct:development
...

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Author: dependabot[bot]