One subscription for all beacon changes.

I mean will this sync the updates for all and stop the subscriptions if beacon has been deactivated?
_Originally posted by @nb9960 in https://github.com/CCExtractor/beacon/pull/97#discussion_r805160175_

As the beacon is subject to lot of changes, having multiple subscriptions can be inefficient. To allow users to subscribe to beacon updates(modifying leader, start/end time etc) and location updates(all users of the beacon), a single stream can be used to achieve this. This will require to change the beacon model.

This issue is open to further discussion, to choose the best way to implement it.

Are yo working on it?
Yes