Adding Symfony 6

Author: Florian Krämer

composer.json

@@ -4,18 +4,18 @@
     "description": "Symfony bundle for the Problem Details for HTTP APIs RFC",
     "require": {
         "php": "^8.2",
-        "symfony/http-kernel": "~7.0",
-        "symfony/serializer": "~7.0",
-        "symfony/uid": "~7.0",
-        "symfony/validator": "~7.0"
+        "symfony/http-kernel": "~7.0|~6.0",
+        "symfony/serializer": "~7.0|~6.0",
+        "symfony/uid": "~7.0|~6.0",
+        "symfony/validator": "~7.0|~6.0"
     },
     "require-dev": {
         "infection/infection": "^0.29.10",
         "phpmd/phpmd": "^2.5",
         "phpstan/phpstan": "^2.0",
         "phpunit/phpunit": "^11.5.0",
         "squizlabs/php_codesniffer": "^3.7.2",
-        "symfony/yaml": "^7.2"
+        "symfony/yaml": "^7.2|^6.0"
     },
     "license": "MIT",
     "autoload": {