Fix typo (#4512)

Author: mairaw

samples/snippets/visualbasic/VS_Snippets_Wpf/DataTemplatingIntro_snip/visualbasic/window1.xaml

@@ -72,7 +72,7 @@
       </ItemsControl.ItemsPanel>
       <!--Use the ItemTemplate to set a DataTemplate to define
           the visualization of the data objects. This DataTemplate
-          specifies that each data object appears with the Proriity
+          specifies that each data object appears with the Priority
           and TaskName on top of a silver ellipse.-->
       <ItemsControl.ItemTemplate>
         <DataTemplate>