Add hardcoded override to ElectionScore (#455)

* Add hardcoded override to ElectionScore so that we can give it the traits it needs

* cargo fmt + another comment

* copy over custom trait impls too

codegen/src/api/mod.rs

@@ -147,6 +147,12 @@ impl RuntimeGenerator {
                 "frame_support::traits::misc::WrapperKeepOpaque",
                 parse_quote!(::subxt::WrapperKeepOpaque),
             ),
+            // We override this because it's used as a key in a BTreeMap, and so we
+            // need to implement some extra derives for it for that to compile.
+            (
+                "sp_npos_elections::ElectionScore",
+                parse_quote!(::subxt::ElectionScore),
+            ),
         ]
         .iter()
         .map(|(path, substitute): &(&str, syn::TypePath)| {