Add parallel testing to GitHub action phpunit

Author: korridor

.github/workflows/phpunit.yml

@@ -52,7 +52,7 @@ jobs:
           php artisan passport:keys
 
       - name: "Run PHPUnit"
-        run: php artisan test --stop-on-failure --coverage-text --coverage-clover=coverage.xml
+        run: php artisan test --parallel --stop-on-failure --coverage-text --coverage-clover=coverage.xml
 
       - name: "Upload coverage reports to Codecov"
         uses: codecov/[email protected]