Client: fix command get script code

src/proto_alpha/lib_client_commands/client_proto_context_commands.ml

@@ -131,9 +131,9 @@ let commands () =
         | Some { code ; storage = _ } ->
             match Script.force_decode code with
             | Error errs -> cctxt#error "%a" (Format.pp_print_list ~pp_sep:Format.pp_print_newline Alpha_environment.Error_monad.pp) errs
-            | Ok code ->
+            | Ok (code, _) ->
                 begin cctxt#answer "%a" Michelson_v1_printer.print_expr_unwrapped code >>= fun () ->
-                  return ()
+                  return_unit
                 end
       end ;