chore: rename demo class names.

src/Shared/HandyControlDemo_Shared/UserControl/Controls/PinBoxDemo.xaml

@@ -1,4 +1,4 @@
-<UserControl x:Class="HandyControlDemo.UserControl.PinBoxDemoCtl"
+<UserControl x:Class="HandyControlDemo.UserControl.PinBoxDemo"
              xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
              xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
              xmlns:hc="https://handyorg.github.io/handycontrol"
@@ -6,8 +6,8 @@
     <hc:TransitioningContentControl>
         <hc:UniformSpacingPanel Spacing="16" Orientation="Vertical" Margin="32" VerticalAlignment="Center" hc:PinBox.Completed="PinBox_OnCompleted">
             <hc:PinBox Length="4" Password="1234"/>
-            <hc:PinBox Length="4" Password="1234" Name="PinBoxDemo" IsSafeEnabled="False"/>
-            <TextBox Text="{Binding UnsafePassword,ElementName=PinBoxDemo,UpdateSourceTrigger=PropertyChanged}"/>
+            <hc:PinBox Length="4" Password="1234" Name="pinBoxDemo" IsSafeEnabled="False"/>
+            <TextBox Text="{Binding UnsafePassword,ElementName=pinBoxDemo,UpdateSourceTrigger=PropertyChanged}"/>
             <hc:PinBox Length="6" Password="123456" PasswordChar="❤"/>
         </hc:UniformSpacingPanel>
     </hc:TransitioningContentControl>