Unused `using OriginalType`

[CoinFuMasterShifu]

This line is unused:

internal/from_str_vec.hpp:24:9: warning: typedef 'using OriginalType = typename rfl::tuple_element<i, typename std::remove_cvref<typename NamedTupleType::Fields>::type>::type::Type' locally defined but not used [-Wunused-local-typedefs]
   24 |   using OriginalType = typename FieldType::Type;
      |         ^~~~~~~~~~~~