Update phpstan/phpstan-phpunit requirement from 2.0.7 to 2.0.8 (#54)

Updates the requirements on [phpstan/phpstan-phpunit](https://github.com/phpstan/phpstan-phpunit) to permit the latest version.
- [Release notes](https://github.com/phpstan/phpstan-phpunit/releases)
- [Commits](phpstan/phpstan-phpunit@2.0.7...2.0.8)

---
updated-dependencies:
- dependency-name: phpstan/phpstan-phpunit
  dependency-version: 2.0.8
  dependency-type: direct:development
...

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

Author: dependabot[bot]

composer.json

@@ -41,7 +41,7 @@
         "phpspec/prophecy-phpunit": "^2.0",
         "phpstan/extension-installer": "^1.4",
         "phpstan/phpstan": "2.1.32",
-        "phpstan/phpstan-phpunit": "2.0.7",
+        "phpstan/phpstan-phpunit": "2.0.8",
         "phpunit/phpunit": "^10 || ^11 || ^12",
         "psalm/plugin-phpunit": "0.19.3",
         "rector/rector": "2.2.8",