use minimum config as sample.

Author: JAMES FUQIAN

server/sample-bluebutton-config.json

@@ -3,10 +3,5 @@
     "client_id": "<client_id>",
     "client_secret": "<client_secret>",
     "callback_url": "http://localhost:3001/api/bluebutton/callback/",
-    "version": 2,
-    "retry_settings": {
-        "total": 3,
-        "backoff_factor": 5,
-        "status_forcelist": [500, 502, 503, 504]
-    }
+    "version": 2
 }