Fix GDScript export hint for Navigation2D layer names

(cherry picked from commit d955d4a1c15409f611cc11f54599dc4dc7858bac)

modules/gdscript/gdscript_parser.cpp

@@ -4310,7 +4310,7 @@ void GDScriptParser::_parse_class(ClassNode *p_class) {
 											_set_error("Expected \")\" in the layers 2D navigation hint.");
 											return;
 										}
-										current_export.hint = PROPERTY_HINT_LAYERS_2D_PHYSICS;
+										current_export.hint = PROPERTY_HINT_LAYERS_2D_NAVIGATION;
 										break;
 									}