Fix GitHub Actions workflow for Laravel 12 compatibility

Update Orchestra Testbench version to v10 for Laravel 12 matrix builds

Author: iamgerwin

.github/workflows/run-tests.yml

@@ -21,7 +21,7 @@ jobs:
           - laravel: 11.*
             testbench: ^9.0
           - laravel: 12.*
-            testbench: ^9.0
+            testbench: ^10.0
 
     name: P${{ matrix.php }} - L${{ matrix.laravel }} - ${{ matrix.stability }} - ${{ matrix.os }}