Use proper type in MethodsBuilder::set_attribute

Reviewed By: ndmitchell

Differential Revision: D47173723

fbshipit-source-id: a119876354bd69fbb77a4a84b1863f13d30d85ac

Author: stepancheg

starlark/src/environment/globals.rs

@@ -393,7 +393,7 @@ impl MethodsBuilder {
             name,
             true,
             docstring,
-            Ty::name(value.to_value().get_type()),
+            V::starlark_type_repr(),
             move |_, _| Ok(value.to_value()),
         );
     }