message: Remove redundant strip_and_convert_t
diff: @@ -62,7 +62,7 @@ public:
  using namespace detail;
  using value_type = strip_and_convert_t<T>;
  static_assert(sendable<value_type>);
  - storage_size_ += padded_size_v<strip_and_convert_t<value_type>>;
  + storage_size_ += padded_size_v<value_type>;
  types_.push_back(type_id_v<value_type>);
  elements_.emplace_back(make_message_builder_element(std::forward<T>(x)));
  return *this;
  