Bump phpunit/phpunit from 9.6.29 to 12.4.2 (#51)

* Bump phpunit/phpunit from 9.6.29 to 12.4.2

Bumps [phpunit/phpunit](https://github.com/sebastianbergmann/phpunit) from 9.6.29 to 12.4.2.
- [Release notes](https://github.com/sebastianbergmann/phpunit/releases)
- [Changelog](https://github.com/sebastianbergmann/phpunit/blob/12.4.2/ChangeLog-12.4.md)
- [Commits](sebastianbergmann/phpunit@9.6.29...12.4.2)

---
updated-dependencies:
- dependency-name: phpunit/phpunit
  dependency-version: 12.4.2
  dependency-type: direct:development
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

* Upgrade phpunit.xml

---------

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: Jonathan Beliën <dev@jbelien.be>

Author: dependabot[bot]

composer.json

@@ -15,7 +15,7 @@
         "league/oauth2-client": "^2.6"
     },
     "require-dev": {
-        "phpunit/phpunit": "^9.5",
+        "phpunit/phpunit": "^12.4",
         "squizlabs/php_codesniffer": "^4.0",
         "mockery/mockery": "^1.4"
     },