Function AppendNull

cpp/src/arrow/array/builder_binary.h:661–666

\brief Append a single null element

  /// \brief Append a single null element
  Status AppendNull() final {
    ARROW_RETURN_NOT_OK(Reserve(1));
    data_builder_.UnsafeAppend(BinaryViewType::c_type{});
    UnsafeAppendToBitmap(false);
    return Status::OK();
  }

  /// \brief Append a empty element (length-0 inline string)
  Status AppendEmptyValue() final {