Introduce CommAndroidNotificationsEventEmitter native module, capable of sending device token from Java to JavaScript in response to broadcast event

Summary:
This differential introduces native module that will serve as a bridge between CommNotificationsHandler and JavaScript. CommNotificationsHAndler will send broadcasts when device token or foreground notifications arrive. CommAndroidNotificationsEventEmitter will receive those broadcasts and
send appropriate events to JavaScript. At this point it already supports receiving new device token event from CommNotificationsHandler and forwarding it to JavaScript. Using LocalBroadcastManager makes implementation efficient since it bypasses OS.

Test Plan: Build the app. Import the module somwhere in JS from NativeModules and call addListener/removrListener. App shouldn't crash.

Reviewers: tomek, bartek

Reviewed By: tomek, bartek

Subscribers: ashoat, atul

Differential Revision: https://phab.comm.dev/D6271