UPDATE github action test

Author: enricodelazzari

.github/workflows/run-tests.yml

@@ -14,11 +14,14 @@ jobs:
       matrix:
         os: [ubuntu-latest, windows-latest]
         php: [8.1, 8.0]
-        laravel: [9.*]
+        laravel: [9.*, 8.*]
         stability: [prefer-lowest, prefer-stable]
         include:
           - laravel: 9.*
             testbench: 7.*
+          - laravel: 8.*
+            testbench: ^6.23
+
 
     name: P${{ matrix.php }} - L${{ matrix.laravel }} - ${{ matrix.stability }} - ${{ matrix.os }}