Docs: Point to @GDScript in GDscript (script impl)

modules/gdscript/doc_classes/GDScript.xml

@@ -5,7 +5,8 @@
 	</brief_description>
 	<description>
 		A script implemented in the GDScript programming language. The script extends the functionality of all objects that instantiate it.
-		[method new] creates a new instance of the script. [method Object.set_script] extends an existing object, if that object's class matches one of the script's base classes.
+		Calling [method new] creates a new instance of the script. [method Object.set_script] extends an existing object, if that object's class matches one of the script's base classes.
+		If you are looking for GDScript's built-in functions, see [@GDScript] instead.
 	</description>
 	<tutorials>
 		<link title="GDScript documentation index">$DOCS_URL/tutorials/scripting/gdscript/index.html</link>