code: function describeRejectedMessage(rejectedMessage, batch, context) {
    const b = batch || context.batch;
    const state = b && b.states.get(rejectedMessage);
    return `Rejected message (${state && (state.msgDesc || state.recDesc)})`;
  }
docs: A `describeItem` implementation that accepts and describes the arguments passed to a `discardRejectedMessage` function.
  @param {Message} rejectedMessage - the rejected message to be discarded
  @param {Batch} batch - the batch being processed
  @param {StreamConsumerContext} context - the context to use
  @returns {string} a short description of the rejected message