Fix issue with Windows 11 ListViewStyle

Issue in WinUI where Windows 11 ListView does not apply alternate row background until hover.

Microsoft.Toolkit.Uwp.UI/Extensions/ListViewBase/ListViewExtensions.AlternateRows.cs

@@ -211,11 +211,22 @@ namespace Microsoft.Toolkit.Uwp.UI
             if (itemIndex % 2 == 0)
             {
                 itemContainer.Background = GetAlternateColor(sender);
+                var rootBorder = itemContainer.FindDescendant<Border>();
+                if (rootBorder != null)
+                {
+                    rootBorder.Background = GetAlternateColor(sender);
+                }
             }
             else
             {
                 itemContainer.Background = null;
+                
+                var rootBorder = itemContainer.FindDescendant<Border>();
+                if (rootBorder != null)
+                {
+                    rootBorder.Background = null;
+                }
             }
         }
     }
-}
+}