chore: update CI configuration to remove Symfony 8.0 support and add .gitignore files

Author: pforesi

.github/workflows/ci.yml

@@ -8,7 +8,7 @@ jobs:
     strategy:
       matrix:
         php-version: ['8.2', '8.3', '8.4']
-        symfony-version: ['^6.4', '^7.0', '^8.0']
+        symfony-version: ['^6.4', '^7.0']
     steps:
       - uses: actions/checkout@master
       - uses: shivammathur/setup-php@v2