ES Bulk Retry Follow-up Items

[criminosis]

Closes #4529

• Reference the ElasticSearch documentation in the bulk chunker size limit config option
• Cleaning up the population of the ES bulk request path logic
• Submitting bulk request items that are below the configured limit, then throwing for overly large items

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[criminosis]

@li-boxuan & @porunov follow-up PR as requested 👍

[criminosis]

@li-boxuan maybe worth your attention too since one of the follow-ups was your request?