@Override
  public void handlePreparePayload(final Prepare prepare) {
    LOG.trace("Received a Prepare Payload.");
    actionOrBufferMessage(
        prepare,
        currentRound.isPresent() ? currentRound.get()::handlePrepareMessage : (ignore) -> {},
        RoundState::addPrepareMessage);
  }
If the list of validators for the next block to be proposed/imported has changed from the
previous block, log the change. Only log for round 0 (i.e. once per block).

@param qbftRound The current round
consensus/qbft-core/src/main/java/org/hyperledger/besu/consensus/qbft/core/statemachine/QbftBlockHeightManager.java