Laravel 8.x support

Author: timoladoyinbo

.github/workflows/tests.yml

@@ -11,8 +11,10 @@ jobs:
       fail-fast: false
       matrix:
         php: [7.4]
-        laravel: [7.*, 6.*]
+        laravel: [8.*, 7.*, 6.*]
         include:
+          - laravel: 8.*
+            testbench: 6.*
           - laravel: 7.*
             testbench: 5.*
           - laravel: 6.*