Add MonologBundle to require-dev to ensure tests run in CI

Author: camilleislasse

src/mcp-bundle/composer.json

@@ -24,7 +24,8 @@
     "require-dev": {
         "phpstan/phpstan": "^2.1",
         "phpstan/phpstan-strict-rules": "^2.0",
-        "phpunit/phpunit": "^11.5"
+        "phpunit/phpunit": "^11.5",
+        "symfony/monolog-bundle": "^3.10"
     },
     "minimum-stability": "dev",
     "prefer-stable": true,