message: neqo-client: Fix logic in HandlerOld::handle()
  out_file is an Option<Option<File>>, the outer option being if the
  stream exists, and the inner option being if there's an output file
  defined for writing the stream contents to. We need to test the inner
  Option to decide whether to write, not the outer one.
diff: @@ -562,10 +562,10 @@ mod old {
  .expect("Read should succeed");
  let mut have_out_file = false;
  - if let Some(out_file) = out_file {
  + if let Some(Some(out_file)) = out_file {
  have_out_file = true;
  if sz > 0 {
  - out_file.as_ref().unwrap().write_all(&data[..sz])?;
  + out_file.write_all(&data[..sz])?;
  }
  } else if !args.output_read_data {
  println!("READ[{}]: {} bytes", stream_id, sz);
  