Fix phpstan github ci workflow

Author: tigitz

.github/workflows/phpstan.yml

@@ -14,7 +14,7 @@ jobs:
       matrix:
         php: [ "8.1", "8.3" ]
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v4
 
       - name: Setup PHP
         uses: shivammathur/setup-php@v2
@@ -33,4 +33,4 @@ jobs:
         run: composer install -n --prefer-dist
 
       - name: Run PHPStan
-        run: ./vendor/bin/phpstan analyse src -c phpstan.${{ matrix.php }}.neon
+        run: ./vendor/bin/phpstan analyse src -c phpstan.neon