composer(deps-dev): update phpstan/phpstan requirement

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/2.1.x/CHANGELOG.md)
- [Commits](phpstan/phpstan@2.1.1...2.1.2)

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

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

composer.json

@@ -42,7 +42,7 @@
   "require-dev": {
     "nikic/php-parser": "^5.4.0",
     "phpstan/extension-installer": "^1.4.3",
-    "phpstan/phpstan": "^2.1.1",
+    "phpstan/phpstan": "^2.1.2",
     "phpstan/phpstan-deprecation-rules": "^2.0.1",
     "rector/rector": "^2.0.7",
     "rector/type-perfect": "^2.0.2",