LibJS: Use correct MarkedValueList append method

Author: https://github.com/mattco98
Commit: 21064a1883
Pull-request: https://github.com/SerenityOS/serenity/pull/2681
Reviewed-by: https://github.com/linusg

Libraries/LibJS/Runtime/Accessor.h

@@ -64,7 +64,7 @@ public:
         if (!m_setter)
             return;
         MarkedValueList arguments(interpreter().heap());
-        arguments.values().append(setter_value);
+        arguments.append(setter_value);
         interpreter().call(*m_setter, this_value, move(arguments));
     }