message: Don't show update dialog if update request failed
diff: @@ -1265,6 +1265,9 @@ void MainWindow::CheckUpdates(bool forceCheck, UpdateResultMethod callback)
  });
  QObject::connect(req, &QNetworkReply::finished, [this, req, callback]() {
  + if(req->error() != QNetworkReply::NoError)
  + return;
  +
  QString response = QString::fromUtf8(req->readAll());
  statusText->setText(QString());
  