createFinalStep
fun <S : AutoCloseable, K1 : WithStream, T, U : Any> createFinalStep(batchAccumulator: BatchAccumulator<S, K1, T, U>, inputQueue: PartitionedQueue<PipelineEvent<K1, T>>, part: Int, numWorkers: Int): LoadPipelineStepTask<S, K1, T, K1, U>