Allow Symfony 6 components (#8)

Author: relthyg

composer.json

@@ -20,16 +20,16 @@
 
     "require": {
         "php": "^7.1|8.0.*|8.1.*",
-        "symfony/config": "^4.4 | ^5.0",
-        "symfony/dependency-injection": "^4.4 | ^5.0",
-        "symfony/http-foundation": "^4.4 | ^5.0",
-        "symfony/http-kernel": "^4.4 | ^5.0",
+        "symfony/config": "^4.4 | ^5.0 | ^6.0",
+        "symfony/dependency-injection": "^4.4 | ^5.0 | ^6.0",
+        "symfony/http-foundation": "^4.4 | ^5.0 | ^6.0",
+        "symfony/http-kernel": "^4.4 | ^5.0 | ^6.0",
         "doctrine/annotations": "^1.0"
     },
 
     "require-dev": {
         "phpunit/phpunit": "^8.5|^9.0",
-        "symfony/phpunit-bridge": ">=5.0"
+        "symfony/phpunit-bridge": "^5.0 | ^6.0"
     },
 
     "suggest": {