message: fix double free erroe
diff: @@ -410,6 +410,7 @@ void ParquetReader::InitializeSchema(const vector<string> &expected_names, const
  for (auto &type_pair : child_types) {
  names.push_back(type_pair.first);
  return_types.push_back(type_pair.second);
  + union_null_cols.push_back(false);
  }
  // Add generated constant column for filename
  @@ -923,9 +924,6 @@ bool ParquetReader::ScanInternal(ParquetReaderScanState &state, DataChunk &resul
  return false;
  }
  - union_null_cols = union_null_cols.empty() ? vector<bool>(result.ColumnCount(), false) : union_null_cols;
  - D_ASSERT(union_null_cols.size() == result.ColumnCount());
  -
  // see if we have to switch to the next row group in the parquet file
  if (state.current_group < 0 || (int64_t)state.group_offset >= GetGroup(state).num_rows) {
  state.current_group++;
  