fix links

docs/modules/contributions/pages/gui/tonegodgui/panel.adoc

@@ -66,4 +66,4 @@ setIgnoreMouse(true);
 
 ----
 
-You can disable any of the default behaviors of the Panel class by using the methods described in the <<jme3/contributions/tonegodgui/element#,Element>> class.
+You can disable any of the default behaviors of the Panel class by using the methods described in the xref:gui/tonegodgui/element.adoc[Element] class.

docs/modules/contributions/pages/gui/tonegodgui/window.adoc

@@ -59,7 +59,7 @@ Window win = new Window(screen, "win", new Vector2f(15, 15), new Vector2f(400, 3
 
 [NOTE]
 ====
-Once again, default behaviors, such as moving, and resizing can be disabled calling the appropriate setters from the <<jme3/contributions/tonegodgui/element#,Element>> class.
+Once again, default behaviors, such as moving, and resizing can be disabled calling the appropriate setters from the xref:gui/tonegodgui/element.adoc[Element] class.
 ====