Update tests.yml

Author: yzen-dev

.github/workflows/tests.yml

@@ -13,7 +13,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        php: ["8.1"]
+        php: ["8.1", "8.0"]
         dependency-version: [prefer-lowest, prefer-stable]
     name: P${{ matrix.php }} - ${{ matrix.dependency-version }}