Fixed ListViewExtensionsCode.bind file. (#3850)

## Fixes #3849 

## PR Type
What kind of change does this PR introduce?
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- Bugfix 
<!-- - Feature -->
<!-- - Code style update (formatting) -->
<!-- - Refactoring (no functional changes, no api changes) -->
<!-- - Build or CI related changes -->
<!-- - Documentation content changes -->
- Sample app changes 
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## What is the current behavior?
ListViewExtensions sample is broken.


## What is the new behavior?
ListViewExtensions sample app works.


## PR Checklist

Please check if your PR fulfills the following requirements:

- [ ] Tested code with current [supported SDKs](../readme.md#supported)
- [ ] Pull Request has been submitted to the documentation repository [instructions](..\contributing.md#docs). Link: <!-- docs PR link -->
- [ ] Sample in sample app has been added / updated (for bug fixes / features)
    - [ ] Icon has been created (if new sample) following the [Thumbnail Style Guide and templates](https://github.com/windows-toolkit/WindowsCommunityToolkit-design-assets)
- [ ] New major technical changes in the toolkit have or will be added to the [Wiki](https://github.com/windows-toolkit/WindowsCommunityToolkit/wiki) e.g. build changes, source generators, testing infrastructure, sample creation changes, etc...
- [ ] Tests for the changes have been added (for bug fixes / features) (if applicable)
- [ ] Header has been added to all new source files (run *build/UpdateHeaders.bat*)
- [X] Contains **NO** breaking changes

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Author: msftbot[bot]

Microsoft.Toolkit.Uwp.SampleApp/SamplePages/ListViewExtensions/ListViewExtensionsCode.bind

@@ -26,7 +26,7 @@
         ui:ListViewExtensions.Command="{Binding SampleCommand}"
         ui:ListViewExtensions.AlternateColor="#33AAAAAA"
         ui:ListViewExtensions.AlternateItemTemplate="{StaticResource AlternateTemplate}"
-        ui:ListViewExtensions.StretchItemContainerDirection="Both">
+        ui:ListViewExtensions.ItemContainerStretchDirection="Both">
     </ListView>
   </Grid>
 </Page>

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

@@ -31,7 +31,7 @@ public static partial class ListViewExtensions
         /// <summary>
         /// Attached <see cref="DependencyProperty"/> for setting the container content stretch direction on the <see cref="Windows.UI.Xaml.Controls.ListViewBase"/>
         /// </summary>
-        public static readonly DependencyProperty ItemContainerStretchDirectionProperty = DependencyProperty.RegisterAttached("ItemContainerStretchDirection", typeof(ItemContainerStretchDirection), typeof(ListViewExtensions), new PropertyMetadata(null, OnStretchItemContainerDirectionPropertyChanged));
+        public static readonly DependencyProperty ItemContainerStretchDirectionProperty = DependencyProperty.RegisterAttached("ItemContainerStretchDirection", typeof(ItemContainerStretchDirection), typeof(ListViewExtensions), new PropertyMetadata(null, OnItemContainerStretchDirectionPropertyChanged));
 
         /// <summary>
         /// Gets the alternate <see cref="Brush"/> associated with the specified <see cref="Windows.UI.Xaml.Controls.ListViewBase"/>
@@ -154,7 +154,7 @@ private static void ItemTemplateContainerContentChanging(Windows.UI.Xaml.Control
             }
         }
 
-        private static void OnStretchItemContainerDirectionPropertyChanged(DependencyObject sender, DependencyPropertyChangedEventArgs args)
+        private static void OnItemContainerStretchDirectionPropertyChanged(DependencyObject sender, DependencyPropertyChangedEventArgs args)
         {
             Windows.UI.Xaml.Controls.ListViewBase listViewBase = sender as Windows.UI.Xaml.Controls.ListViewBase;
 
@@ -163,17 +163,17 @@ private static void OnStretchItemContainerDirectionPropertyChanged(DependencyObj
                 return;
             }
 
-            listViewBase.ContainerContentChanging -= StretchItemContainerDirectionChanging;
+            listViewBase.ContainerContentChanging -= ItemContainerStretchDirectionChanging;
             listViewBase.Unloaded -= OnListViewBaseUnloaded;
 
             if (ItemContainerStretchDirectionProperty != null)
             {
-                listViewBase.ContainerContentChanging += StretchItemContainerDirectionChanging;
+                listViewBase.ContainerContentChanging += ItemContainerStretchDirectionChanging;
                 listViewBase.Unloaded += OnListViewBaseUnloaded;
             }
         }
 
-        private static void StretchItemContainerDirectionChanging(Windows.UI.Xaml.Controls.ListViewBase sender, ContainerContentChangingEventArgs args)
+        private static void ItemContainerStretchDirectionChanging(Windows.UI.Xaml.Controls.ListViewBase sender, ContainerContentChangingEventArgs args)
         {
             var itemContainer = args.ItemContainer as SelectorItem;
             var stretchDirection = GetItemContainerStretchDirection(sender);
@@ -194,7 +194,7 @@ private static void OnListViewBaseUnloaded(object sender, RoutedEventArgs e)
             Windows.UI.Xaml.Controls.ListViewBase listViewBase = sender as Windows.UI.Xaml.Controls.ListViewBase;
             _itemsForList.Remove(listViewBase.Items);
 
-            listViewBase.ContainerContentChanging -= StretchItemContainerDirectionChanging;
+            listViewBase.ContainerContentChanging -= ItemContainerStretchDirectionChanging;
             listViewBase.ContainerContentChanging -= ItemTemplateContainerContentChanging;
             listViewBase.ContainerContentChanging -= ColorContainerContentChanging;
             listViewBase.Items.VectorChanged -= ColorItemsVectorChanged;