Set cancel_status if it's not None

Signed-off-by: aftermath2 <cxbvnlrzfjwi@protonmail.com>

tests/utils/trade.py

@@ -116,7 +116,9 @@ def cancel_order(self, robot_index=1, cancel_status=None):
         path = reverse("order")
         params = f"?order_id={self.order_id}"
         headers = self.get_robot_auth(robot_index)
-        body = {"action": "cancel", "cancel_status": cancel_status}
+        body = {"action": "cancel"}
+        if cancel_status is not None:
+            body.update({"cancel_status": cancel_status})
         self.response = self.client.post(path + params, body, **headers)
 
     @patch("api.tasks.send_notification.delay", send_notification)