Update xml/System.Drawing.Imaging/DitherType.xml

Co-authored-by: Genevieve Warren <[email protected]>

Author: lonitra

xml/System.Drawing.Imaging/DitherType.xml

@@ -14,7 +14,8 @@
   </Base>
   <Docs>
     <summary>Specifies how images are dithered with a reduced color palette.</summary>
-    <remarks>To be added.</remarks>
+    <remarks>For information about the ordered and spiral dither types, see the <see href="/windows/win32/api/gdipluspixelformats/ne-gdipluspixelformats-dithertype#remarks">remarks for the Win32 DitherType enumeration</see>. The fixed palette types mentioned there correspond to the <see cref="T:System.Drawing.Imaging.PaletteType" /> enumeration.</remarks>
+    <related type="Article" href="/windows/win32/api/gdipluspixelformats/ne-gdipluspixelformats-dithertype">DitherType enumeration (gdipluspixelformats.h)</related>
   </Docs>
   <Members>
     <Member MemberName="DualSpiral4x4">