Fix: Fixed crash from #10467 (#10910)

Author: QuaintMako

src/Files.App/UserControls/SidebarControl.xaml.cs

@@ -448,7 +448,7 @@ private async void Sidebar_ItemInvoked(NavigationView sender, NavigationViewItem
 				return;
 			}
 
-			var navigationPath = args.InvokedItemContainer.Tag.ToString();
+			var navigationPath = args.InvokedItemContainer.Tag?.ToString();
 
 			if (await CheckEmptyDrive(navigationPath))
 				return;