Reset matrix-js-sdk to develop branch, adopt new join/leave signatures

src/utils/test.ts

@@ -472,7 +472,7 @@ export class MockRTCSession extends TypedEventEmitter<
     counters: {},
   };
 
-  public leaveRoomSession: ReturnType<typeof vitest.fn> = vitest
+  public leave: ReturnType<typeof vitest.fn> = vitest
     .fn()
     .mockResolvedValue(undefined);
 
@@ -531,7 +531,7 @@ export class MockRTCSession extends TypedEventEmitter<
     if (value !== prev) this.emit(MembershipManagerEvent.ProbablyLeft, value);
   }
 
-  public async joinRTCSession(): Promise<void> {
+  public async join(): Promise<void> {
     return Promise.resolve();
   }
 }