MatrixRTC: MembershipManager test cases and deprecation of MatrixRTCSession.room (#4713)

* WIP doodles on MembershipManager test cases

* .

* initial membership manager test setup.

* Updates from discussion

* revert renaming comments

* remove unused import

* fix leave delayed event resend test.
It was missing a flush.

* comment out and remove unused variables

* es lint

* use jsdom instead of node test environment

* remove unused variables

* remove unused export

* temp

* review

* fixup tests

* more review

* remove wait for expect dependency

* flatten tests and add comments

* add more leave test cases

* use defer

* remove @jest/environment dependency

* Cleanup awaits and Make mock types more correct.
Make every mock return a Promise if the real implementation does return a pormise.

* remove flush promise dependency

* add linting to matrixrtc tests

* Add fix async lints and use matrix rtc logger for test environment.

* prettier

* change to MatrixRTCSession logger

* make accessing the full room deprecated

* remove deprecated usage of full room

* Clean up the deprecation

---------

Co-authored-by: Hugh Nimmo-Smith <hughns@matrix.org>

spec/unit/matrixrtc/MatrixRTCSessionManager.spec.ts

@@ -32,7 +32,7 @@ import { makeMockRoom, makeMockRoomState, membershipTemplate } from "./mocks";
 describe("MatrixRTCSessionManager", () => {
     let client: MatrixClient;
 
-    beforeEach(async () => {
+    beforeEach(() => {
         client = new MatrixClient({ baseUrl: "base_url" });
         client.matrixRTC.start();
     });