Update App.xaml.cs

Author: ghost1372

dev/DevWinUI.Gallery/App.xaml.cs

@@ -49,6 +49,7 @@ protected override void OnLaunched(LaunchActivatedEventArgs args)
 
         MainWindow.Title = MainWindow.AppWindow.Title = ProcessInfoHelper.ProductNameAndVersion;
         MainWindow.AppWindow.SetIcon("Assets/icon.ico");
+        MainWindow.AppWindow.SetTaskbarIcon("Assets/icon.ico");
 
         MainWindow.Activate();