[8.x] Adds docs regarding dd, ddHeaders, ddSession (#7395)

* Adds docs regarding `dd`, `ddHeaders`, `ddSession`

* Update http-tests.md

Co-authored-by: Taylor Otwell <taylor@laravel.com>

http-tests.md

@@ -185,8 +185,6 @@ After making a test request to your application, the `dump`, `dumpHeaders`, and
 
     namespace Tests\Feature;
 
-    use Illuminate\Foundation\Testing\RefreshDatabase;
-    use Illuminate\Foundation\Testing\WithoutMiddleware;
     use Tests\TestCase;
 
     class ExampleTest extends TestCase
@@ -208,6 +206,33 @@ After making a test request to your application, the `dump`, `dumpHeaders`, and
         }
     }
 
+Alternatively, you may use the `dd`, `ddHeaders`, and `ddSession` methods to dump information about the response and then stop execution:
+
+    <?php
+
+    namespace Tests\Feature;
+
+    use Tests\TestCase;
+
+    class ExampleTest extends TestCase
+    {
+        /**
+         * A basic test example.
+         *
+         * @return void
+         */
+        public function test_basic_test()
+        {
+            $response = $this->get('/');
+
+            $response->ddHeaders();
+
+            $response->ddSession();
+
+            $response->dd();
+        }
+    }
+
 <a name="exception-handling"></a>
 ### Exception Handling