fix(deps): update module github.com/elastic/go-elasticsearch/v8 to v8.15.0

[elastic-renovate-prod[bot]]

This PR contains the following updates:

Package	Type	Update	Change
github.com/elastic/go-elasticsearch/v8	require	minor	v8.14.0 -> v8.15.0

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Release Notes

elastic/go-elasticsearch (github.com/elastic/go-elasticsearch/v8)

### [`v8.15.0`](https://togithub.com/elastic/go-elasticsearch/compare/v8.14.0...v8.15.0) [Compare Source](https://togithub.com/elastic/go-elasticsearch/compare/v8.14.0...v8.15.0)

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