added WinRT bindable property attribute

Author: w-ahmad

src/TableViewCell.cs

@@ -23,6 +23,9 @@ namespace WinUI.TableView;
 [TemplateVisualState(Name = VisualStates.StateCurrent, GroupName = VisualStates.GroupCurrent)]
 [TemplateVisualState(Name = VisualStates.StateSelected, GroupName = VisualStates.GroupSelection)]
 [TemplateVisualState(Name = VisualStates.StateUnselected, GroupName = VisualStates.GroupSelection)]
+#if WINDOWS
+[WinRT.GeneratedBindableCustomProperty]
+#endif
 public partial class TableViewCell : ContentControl
 {
     private TableViewColumn? _column;
@@ -445,7 +448,7 @@ internal void SetElement()
             element.Style = boundColumn.ElementStyle;
         }
 
-        Content = element;
+            Content = element;
 
 #if !WINDOWS
         DispatcherQueue.TryEnqueue(async () =>

src/TableViewRowHeader.cs

@@ -9,6 +9,9 @@ namespace WinUI.TableView;
 /// <summary>
 /// Represents a header for row in TableView.
 /// </summary>
+#if WINDOWS
+[WinRT.GeneratedBindableCustomProperty]
+#endif
 public partial class TableViewRowHeader : ContentControl
 {
     private ContentPresenter? _contentPresenter;