message: Do not use `_join_handle` in test
diff: @@ -539,7 +539,7 @@ mod tests {
  while 0 != network.crank_all(&mut rng).await {}
  // Start a background task that connects to the unix socket and sends a few requests down.
  - let join_handle = tokio::spawn(async move {
  + let _join_handle = tokio::spawn(async move {
  eprintln!("connecting");
  let mut stream = UnixStream::connect(socket_path)
  .await
  