edec6e7558
This patch makes `RoomListService::room` synchronous. It no longer reads a `SlidingSyncRoom` from `SlidingSync`, then it not needs to be async anymore. This patch replaces the `RwLock` of `RoomListService::rooms` from `tokio::sync` to `std::sync`. The patch updates all calls to `RoomListService::room` to remove the `.await` point.