Allow Symfony 8.x to be used (#57)

Author: mpdude

.github/workflows/tests.yml

@@ -14,8 +14,9 @@ jobs:
             matrix:
                 include:
                     - { php-version: 8.1, symfony-version: 6.4.*, dependency-version: prefer-lowest }
-                    - { php-version: 8.1, symfony-version: 6.4.*, dependency-version: prefer-stable }
-                    - { php-version: 8.3, symfony-version: 7.*, dependency-version: prefer-stable }
+                    - { php-version: 8.3, symfony-version: 6.4.*, dependency-version: prefer-stable }
+                    - { php-version: 8.4, symfony-version: 7.*, dependency-version: prefer-stable }
+                    - { php-version: 8.4, symfony-version: 8.*, dependency-version: prefer-stable }
         name: PHPUnit (PHP ${{ matrix.php-version }}, Symfony version lock ${{ matrix.symfony-version }}, ${{ matrix.dependency-version }})
         steps:
             -   uses: actions/checkout@v4

composer.json

@@ -28,9 +28,9 @@
     "require": {
         "php": ">= 8.1",
         "ext-json": "*",
-        "symfony/config": "^6.4 || ^7.3",
-        "symfony/dependency-injection": "^6.4 || ^7.3",
-        "symfony/http-kernel": "^6.4 || ^7.3",
+        "symfony/config": "^6.4 || ^7.3 || ^8.0",
+        "symfony/dependency-injection": "^6.4 || ^7.3 || ^8.0",
+        "symfony/http-kernel": "^6.4 || ^7.3 || ^8.0",
         "twig/twig": "^2.0 || ^3.0"
     },
     "require-dev": {