Fixing telescope push timestamp check

checks/remotesettings/push_timestamp.py

@@ -10,8 +10,10 @@
 
 import websockets
 
+from operator import attrgetter
 from telescope.typings import CheckResult
 from telescope.utils import utcfromtimestamp, utcnow
+from datetime import datetime
 
 from .utils import KintoClient
 
@@ -43,6 +45,10 @@ async def get_push_timestamp(uri) -> str:
 async def get_remotesettings_timestamp(uri) -> str:
     client = KintoClient(server_url=uri)
     entries = await client.get_monitor_changes(bust_cache=True)
+
+    # sort by timestamp desc as the records are returned by bucket/collection
+    entries.sort(key=lambda e: e["last_modified"], reverse=True)
+
     # Some collections are excluded (eg. preview)
     # https://github.com/mozilla-services/cloudops-deployment/blob/master/projects/kinto/puppet/modules/kinto/templates/kinto.ini.erb
     matched = [e for e in entries if "preview" not in e["bucket"]]