[DOC] Update terminate_after documentation with explanation of edge cases when using size=0 and track_total_hits=true

[jed326]

What do you want to do?

• Request a change to existing documentation
• Add new documentation
• Report a technical problem with the documentation
• Other

Tell us about your request. Provide a summary of the request and all versions that are affected.
Docs: https://opensearch.org/docs/1.2/opensearch/rest-api/search/

There is a special edge case when terminate_after=true, size=0, and track_total_hits=true are used together where the hits.count value may be greater than the terminate_after value due to a time optimization use in this scenario.

What other resources are available? Provide links to related issues, POCs, steps for testing, etc.

For more details see: opensearch-project/OpenSearch#10435 (comment)

[hdhalter]

Thanks for this feedback, @jed326! Please note that we are no longer maintaining the 1.2 documentation. We are maintaining the latest minor version of the major versions (2.11 and 1.3). Is this an issue in those versions? If so, can you please create a PR to update the page?

[jed326]

Hey @hdhalter apologies for the confusion I didn't mean to link to 1.2 specifically. This is actually an edge case that has existed since OpenSearch 2.2. Ideally we would add this documentation to all versions after 2.2, but if we are only maintaining the latest minor version docs then we can add it beginning in 2.11. I can follow-up with a PR for this in some time. Thanks!

[hdhalter]

In some cases we do backport to previous versions, like in the case of incorrect information, so we can backport this one to 2.2.