Update actions configuration.

Author: olsgreen

.github/workflows/run_tests.yml

@@ -8,12 +8,9 @@ jobs:
 
     strategy:
       matrix:
-        php: [7.2, 7.3, 7.4, 8.0]
-        laravel: [6.*]
+        php: [7.3, 7.4, 8.0]
+        laravel: [7.*, 8.*]
         dependency-version: [prefer-stable, prefer-lowest]
-        include:
-          - laravel: 6.*
-            testbench: 4.*
 
     name: PHP ${{ matrix.php }}  - Laravel ${{ matrix.laravel }} - Testbench ${{ matrix.testbench }} (${{ matrix.dependency-version }})