message: rewrite complex match to and_then
  Closes:
  Approved by: darioncassel
diff: @@ -413,11 +413,7 @@ async fn handle_inbound_substream<TSubstream>(
  )
  .timeout(timeout)
  .map_err(Into::<RpcError>::into)
  - .map(|r| match r {
  - Ok(Ok(_x)) => Ok(()),
  - Ok(Err(e)) => Err(e),
  - Err(e) => Err(e),
  - })
  + .map(|r| r.and_then(|x| x))
  .await;
  // Log any errors.
  