fix totalTime type typo

Author: markdentoom

hypernode_api_python/client.py

@@ -636,7 +636,7 @@ def get_active_branchers(self, app_name):
         Example:
         >    client.get_active_branchers('yourhypernodeappname').json()
         >    {
-        >        "totalTime": 9417.327453,
+        >        "totalTime": "9417.327453",
         >        "totalAmountSpent": 9417.327453,
         >        "branchers": [
         >            {