Add missing keys in scheduled notifications
Error logs from notifications-routing pod:
2021-12-15 21:20:23,513 ERROR root An exception happened while processing the message
Traceback (most recent call last):
File "/app/notifications_routing/router.py", line 38, in on_message
self.process_message(self.read_message(message))
File "/app/notifications_routing/router.py", line 71, in read_message
str(OutputMessageKeys.PRIVATE): message_json[str(InputMessageKeys.PRIVATE)],
KeyError: 'private'