Added more tests for change merged and comment added events

tests/test_comment_added.py

@@ -0,0 +1,13 @@
+import json
+
+from tests import base
+
+
+class TestCommentAdded(base.BaseTestCase):
+
+    def test_recheck(self):
+        result = self._send_and_get_response('comment-added')
+
+        self.assertTrue(result)
+        result = json.loads(result)
+        self.assertEqual(result['labels']['Verified'], 1)