private boolean hasDuplicateAuthors(
      final Collection<SignedData<PreparePayload>> preparePayloads) {
    final long distinctAuthorCount =
        preparePayloads.stream().map(SignedData::getAuthor).distinct().count();

    if (distinctAuthorCount != preparePayloads.size()) {
      LOG.info("Invalid PreparePayloads list, multiple payloads from the same author.");
      return true;
    }
    return false;
  }
Validate round change.

@param msg the msg
@return the boolean
consensus/ibft/src/main/java/org/hyperledger/besu/consensus/ibft/validation/RoundChangePayloadValidator.java