Fixed incorrect Texture type in example

tutorials/plugins/editor/making_plugins.rst

@@ -250,7 +250,7 @@ dialog. For that, change the ``custom_node.gd`` script to the following:
             // Initialization of the plugin goes here.
             // Add the new type with a name, a parent type, a script and an icon.
             var script = GD.Load<Script>("MyButton.cs");
-            var texture = GD.Load<Texture>("icon.png");
+            var texture = GD.Load<Texture2D>("icon.png");
             AddCustomType("MyButton", "Button", script, texture);
         }