Qt: Raise updater window if already shown

Too bad it won't work on Wayland. I'm trying to give a good
user experience on a platform that is so developer hostile.

src/duckstation-qt/mainwindow.cpp

@@ -2997,7 +2997,10 @@ void MainWindow::checkForUpdates(bool display_message)
   }
 
   if (m_auto_updater_dialog)
+  {
+    QtUtils::ShowOrRaiseWindow(m_auto_updater_dialog);
     return;
+  }
 
   m_auto_updater_dialog = new AutoUpdaterWindow();
   connect(m_auto_updater_dialog, &AutoUpdaterWindow::updateCheckCompleted, this, &MainWindow::onUpdateCheckComplete);