private String toLogString(final Collection<NewBlockHash> newBlockHashs) {
    return newBlockHashs.stream()
        .map(NewBlockHash::toString)
        .collect(Collectors.joining(", ", "[", "]"));
  }
Try to request the lowest ancestor for the given pending block or process the descendants if
the ancestor is already in the chain
ethereum/eth/src/main/java/org/hyperledger/besu/ethereum/eth/sync/BlockPropagationManager.java