Update test suite

Author: sc0ttkclark

.github/workflows/tests-php.yml

@@ -39,7 +39,7 @@ jobs:
       - name: Configure PHP environment
         uses: shivammathur/setup-php@v2
         with:
-          php-version: 7.4
+          php-version: 8.0
       # ------------------------------------------------------------------------------
       # Checkout slic
       # ------------------------------------------------------------------------------