@Override
  public void writeTo(final RLPOutput rlpOutput) {
    rlpOutput.startList();
    writeConsensusRound(rlpOutput);
    rlpOutput.writeBytes(digest);
    rlpOutput.endList();
  }
Read from rlp input and return prepare payload.

@param rlpInput the rlp input
@return the prepare payload
consensus/qbft-core/src/main/java/org/hyperledger/besu/consensus/qbft/core/payload/PreparePayload.java