Add Symfony 6 to the CI workflow

Author: ste93cry

.github/workflows/tests.yaml

@@ -27,9 +27,16 @@ jobs:
           - 3.4.*
           - 4.4.*
           - 5.*
+          - 6.*
         dependencies:
           - highest
         exclude:
+          - php: '7.2'
+            symfony-version: 6.*
+          - php: '7.3'
+            symfony-version: 6.*
+          - php: '7.4'
+            symfony-version: 6.*
           - php: '8.0'
             symfony-version: 3.4.*
           - php: '8.1'