Add setting for allow_leading_wildcard to search

[nevins-b]

Description

Allow for setting, disabling, allow_leading_wildcard on a search

Issues Resolved

List any issues this PR will resolve, e.g. Closes [...].

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[dblock]

Thanks! Happy to take this with some tests, please?

[nevins-b]

@dblock Sure, I didn't see a place to add tests. I could add something to the benchmark tests but that didn't feel right. Suggestion of where I would add some?

[dblock]

Not a go expert nor have I looked in detail into opensearch-go to say where those tests should go, but looks like there's a bunch of tests that are running (https://github.com/opensearch-project/opensearch-go/runs/6070092469?check_suite_focus=true). I'd like us not to merge untested code, so if you need to introduce a new set of tests and just test this one addition, let's do it?

[VachaShah]

@nevins-b Thank you for this PR! May be the tests can go here?

[wbeckler]

Hi @nevins-b, do you think you'll want this merged? If nobody adds tests or moves this forward, I propose we close this PR.

[Jakob3xD]

While looking into the PR I noticed that allow_leading_wildcard does not seems to be a parameter for a search request.
allow_leading_wildcard is a filed of query_string in the search body. The body is given via the user so adding this to search prams would not work. https://opensearch.org/docs/latest/query-dsl/full-text/query-string/

I suggest closing the PR. @wbeckler

[wbeckler]

I'm okay with closing this. Any other maintainers have a thought?