creating multiple batch operations for entities won't scale

Problem/Motivation

This won't scale to very large numbers of entities:

    $iterations = (int) ($total_entities / $limit);
    $operation_start_timestamp = $this->time->getRequestTime();
    for ($iteration = 0; $iteration < $iterations; $iteration++) {

It's better to use only one operation, and have it return to the batch that it needs to re-run until there are no items left to process.

Steps to reproduce

Proposed resolution

Remaining tasks

User interface changes

API changes

Data model changes