Update Editor icons Setup Docs with Color conversion Note (#11159)

* Update Editor icons Setup Docs with Color conversion Note #108770

contributing/development/editor/creating_icons.rst

@@ -43,6 +43,11 @@ This is to ensure the icon always displays with a sufficient contrast rate.
 Try to restrict your icon's color palette to colors found in the list above.
 Otherwise, your icon may become difficult to read on a light background.
 
+.. note::
+	To enable color conversion for light editor themes:
+		1. :ui:`Import > Import As > Texture2D`
+		2. Set ``editor/convert_colors_with_editor_theme`` to ``true``
+
 Icon optimization
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