Response model now handles the 204 no content

tests/test_requests.py

@@ -104,6 +104,7 @@ def test_json():
 
     assert results.get('test') == True
 
+
 def test_empty_json():
     app = Sanic('test_json')
 
@@ -114,7 +115,7 @@ def test_empty_json():
 
     request, response = app.test_client.get('/')
     assert response.status == 200
-    assert response.text == ''
+    assert response.text == 'null'
 
 
 def test_invalid_json():