Fix warnings and code cleanup/fixes (#13570)

Content.Client/Paper/UI/StampWidget.xaml

@@ -1,14 +1,8 @@
 <paper:StampWidget xmlns="https://spacestation14.io"
     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
-    xmlns:controls="clr-namespace:Content.Client.UserInterface.Controls"
     xmlns:style="clr-namespace:Content.Client.Stylesheets"
     xmlns:gfx="clr-namespace:Robust.Client.Graphics;assembly=Robust.Client"
     xmlns:paper="clr-namespace:Content.Client.Paper.UI" HorizontalAlignment="Center" Margin="6">
-    <!--
-    <TextureButton Margin="6 6 6 2" MinSize="24 12"
-        TexturePath="/Textures/Interface/Nano/nano_stamp.192dpi.png">
-    -->
-
 
     <BoxContainer Orientation="Vertical">
         <PanelContainer>