Update phpstan/phpstan requirement from ^2.0.1 to ^2.0.3

Updates the requirements on [phpstan/phpstan](https://github.com/phpstan/phpstan) to permit the latest version.
- [Release notes](https://github.com/phpstan/phpstan/releases)
- [Changelog](https://github.com/phpstan/phpstan/blob/2.0.x/CHANGELOG.md)
- [Commits](phpstan/phpstan@2.0.1...2.0.3)

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

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

composer.json

@@ -18,7 +18,7 @@
   "require-dev": {
     "doctrine/coding-standard": "^12.0",
     "phpunit/phpunit": "^11.4.3",
-    "phpstan/phpstan": "^2.0.1"
+    "phpstan/phpstan": "^2.0.3"
   },
   "autoload": {
     "psr-4": {