message: Add comment about potential optimization
diff: @@ -483,6 +483,9 @@ pub(super) async fn get_block_with_metadata<REv: ReactorEventT>(
  return Ok(block_with_metadata);
  }
  + // TODO: Potential optimization: We might want to make the `GetBlock` actually return the
  + // highest disjoint sequence of block heights, so we don't need to request it again inside the
  + // `missing_block_or_state_root_error` function.
  let error = match maybe_id {
  Some(BlockIdentifier::Hash(block_hash)) => common::missing_block_or_state_root_error(
  effect_builder,
  