allow Symfony 6 (#6)

Author: dmaicher

.travis.yml

@@ -22,7 +22,7 @@ matrix:
 
     - php: 8.0
       env:
-        - SYMFONY_REQUIRE="5.2.*"
+        - SYMFONY_REQUIRE="6.0.*"
         - STABILITY=dev
 
 before_install:

composer.json

@@ -16,13 +16,13 @@
     "require": {
         "php": "^7.1 || ^8.0",
         "solarium/solarium": "^5.2 || ^6.0",
-        "symfony/framework-bundle": "^4.4 || ^5.2"
+        "symfony/framework-bundle": "^4.4 || ^5.2 || ^6.0"
     },
     "require-dev": {
         "phpstan/phpstan": "^0.12",
         "phpunit/phpunit": "^7.5 || ^8.5 || ^9.4",
-        "symfony/phpunit-bridge": "^5.2",
-        "symfony/stopwatch": "^4.4 || ^5.2"
+        "symfony/phpunit-bridge": "^5.2 || ^6.0",
+        "symfony/stopwatch": "^4.4 || ^5.2 || ^6.0"
     },
     "autoload": {
         "psr-4": {