reset method
Closes both ends of the stream
Implementation
@override
Future<void> reset() async {
if (_reset != null) return;
_reset = const ResetException('stream reset');
_sendFlag(FrameFlag.resetStream);
_readQueue.clear();
if (!_finAck.isCompleted) _finAck.completeError(_reset!);
_wakeReaders();
_closeChannel();
}