clearCache method
Implementation
@override
Future<void> clearCache() => transaction(() async {
await _roomsBox.clear();
await _accountDataBox.clear();
await _roomStateBox.clear();
await _roomMembersBox.clear();
await _eventsBox.clear();
await _timelineFragmentsBox.clear();
await _outboundGroupSessionsBox.clear();
await _presencesBox.clear();
await _clientBox.delete('prev_batch');
});