Update README.md

Author: barryvdh

README.md

@@ -1,7 +1,7 @@
 # CORS for PHP (using the Symfony HttpFoundation)
 
 [![Unit Tests](https://github.com/fruitcake/php-cors/actions/workflows/run-tests.yml/badge.svg)](https://github.com/fruitcake/php-cors/actions)
-[![PHPStan Level 9](https://img.shields.io/badge/PHPStan-Level%209-blue)](https://github.com/fruitcake/php-cors/actions)
+[![PHPStan Level 9](https://img.shields.io/badge/PHPStan-Level%2010-blue)](https://github.com/fruitcake/php-cors/actions)
 [![Code Coverage](https://img.shields.io/badge/CodeCoverage-100%25-brightgreen)](https://github.com/fruitcake/php-cors/actions/workflows/run-coverage.yml)
 [![Packagist License](https://img.shields.io/badge/Licence-MIT-blue)](http://choosealicense.com/licenses/mit/)
 [![Latest Stable Version](https://img.shields.io/packagist/v/fruitcake/php-cors?label=Stable)](https://packagist.org/packages/fruitcake/php-cors)