[ES 9.0] Remove body workaround (@elastic/obs-ux-management-team)

[afharo]

Summary

Follow up to #213375: The latest version of the ES client fixed the issue elastic/elasticsearch-js#2584.

We should be able to remove all usages of // @ts-expect-error elasticsearch@9.0.0 https://github.com/elastic/elasticsearch-js/issues/2584.

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[elasticmachine]

💚 Build Succeeded

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• Commit: d0f07b0

Metrics [docs]

✅ unchanged

cc @afharo

[elasticmachine]

Pinging @elastic/obs-ux-management-team (Team:obs-ux-management)