ResourceStringExtension Sample: adding additional function notation that accomodates no optional value in x:Bind compiled function

Author: HerrickSpencer

Microsoft.Toolkit.Uwp.SampleApp/SamplePages/ResourceString/ResourceStringXaml.bind

@@ -44,6 +44,11 @@
                Style="{StaticResource BodyTextBlockStyle}">
                 You can alternatively get a greeting using x:Bind for optimized compiled bind:
             </TextBlock>
+            <TextBlock
+               TextWrapping="Wrap" Margin="10,10,0,0"
+               Style="{StaticResource BodyTextBlockStyle}">
+                {x:Bind ui:ResourceStringExtension.GetValue('HelloText')}
+            </TextBlock>
             <TextBlock
                TextWrapping="Wrap" Margin="10,10,0,0"
                Style="{StaticResource BodyTextBlockStyle}">