Add missing required Symfony packages (#237)

Author: wouterj

src/symfony/composer.json

@@ -28,6 +28,9 @@
         "symfony/framework-bundle": "^6.0",
         "symfony/http-client": "^6.0",
         "symfony/psr-http-message-bridge": "^2.0",
+        "symfony/security-bundle": "^6.0",
+        "symfony/serializer": "^6.0",
+        "symfony/validator": "^6.0",
         "web-auth/webauthn-lib": "self.version",
         "web-token/jwt-signature": "^3.0"
     },