Remove map_err that isn't needed anymore

Author: rklaehn

src/api/downloader.rs

@@ -143,7 +143,6 @@ async fn handle_download_split_impl(
                 let (tx, rx) = tokio::sync::mpsc::channel::<(usize, DownloadProgessItem)>(16);
                 progress_tx.send(rx).await.ok();
                 let sink = TokioMpscSenderSink(tx)
-                    .with_map_err(|_| irpc::channel::SendError::ReceiverClosed)
                     .with_map(move |x| (id, x));
                 let res = execute_get(&pool, Arc::new(request), &providers, &store, sink).await;
                 (hash, res)