chore(deps-dev): update phpunit/phpunit requirement

Updates the requirements on [phpunit/phpunit](https://github.com/sebastianbergmann/phpunit) to permit the latest version.
- [Changelog](https://github.com/sebastianbergmann/phpunit/blob/11.0.3/ChangeLog-11.0.md)
- [Commits](sebastianbergmann/phpunit@10.5.0...11.0.3)

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

Signed-off-by: dependabot[bot] <[email protected]>

composer.json

@@ -14,7 +14,7 @@
     },
     "require-dev": {
         "charonlab/coding-standard": "1.2.x-dev",
-        "phpunit/phpunit": "10.5.x-dev",
+        "phpunit/phpunit": "11.0.3",
         "vimeo/psalm": "6.x-dev"
     },
     "minimum-stability": "dev",