Crash on processBeaconEvents due to null room in notificationTimeline

[sdb-dev]

Describe the bug
When loading the client timeline set data, processBeaconEvents is called on the matrix events for the notification timeline. However, notification timeline has no room associated with it.

The processBeaconEvents function expects a room if there are any matrix events.

Here is the callback on the sync event:

And the call to processBeaconEvents:

To Reproduce
Steps to reproduce the behavior:
Create / start the client
Create a notification timelineset
Request timeline notifications

Desktop (please complete the following information):

• OS: Windows 10
• Browser Chrome
• Version 103

This is not an issue in version 16 of the SDK. It is present in 17, 18, and 19.