Bumping async_stream causes test failures

[poljar]

As discovered in #4596, updating async-stream cause some tests to fail.

The reason the identity_status_changes test fail is because the event handler for the m.room.member event registered over here:

matrix-rust-sdk/crates/matrix-sdk/src/room/identity_status_changes.rs

Lines 178 to 193 in 8d27b0c

	fn wrap_room_member_events(
	room: &Room,
	) -> (EventHandlerDropGuard, impl Stream<Item = RoomIdentityChange>) {
	let own_user_id = room.own_user_id().to_owned();
	let room_id = room.room_id();
	let (sender, receiver) = mpsc::channel(16);
	let handle =
	room.client.add_room_event_handler(room_id, move |event: SyncRoomMemberEvent| async move {
	if *event.state_key() == own_user_id {
	return;
	}
	let _: Result<_, _> = sender.send(RoomIdentityChange::SyncRoomMemberEvent(event)).await;
	});
	let drop_guard = room.client.event_handler_drop_guard(handle);
	(drop_guard, ReceiverStream::new(receiver))
	}

isn't called anymore. As we can see, we create a drop guard for the event handler. So once the guard is dropped the handler is removed. The drop guard gets moved into a stream over here:

matrix-rust-sdk/crates/matrix-sdk/src/room/identity_status_changes.rs

Lines 93 to 123 in 8d27b0c

	let (drop_guard, room_member_events) = wrap_room_member_events(&room);
	let mut unprocessed_stream = combine_streams(identity_updates, room_member_events);
	let own_user_id = room.client.user_id().ok_or(Error::InsufficientData)?.to_owned();
	let mut state = IdentityStatusChanges {
	room_identity_state: RoomIdentityState::new(room).await,
	_drop_guard: drop_guard,
	};
	Ok(stream!({
	let mut current_state =
	filter_for_initial_update(state.room_identity_state.current_state(), &own_user_id);
	if !current_state.is_empty() {
	current_state.sort();
	yield current_state;
	}
	while let Some(item) = unprocessed_stream.next().await {
	let mut update = filter_non_self(
	state.room_identity_state.process_change(item).await,
	&own_user_id,
	);
	if !update.is_empty() {
	update.sort();
	yield update;
	}
	}
	}))
	}
	}

This means that the handler should be alive as long as the stream is alive, but as it seems something changed between async_stream version 0.3.5 and 0.3.6 and the drop guard gets dropped before the stream is.

Downgrading async_stream fixes the issue. The only relevant change seems to be in this PR: tokio-rs/async-stream@97d1d3e.