Cleanup - Typescript some of src/legacy/server/index_patterns

[alexwizp]

Part of #44190.

Summary

Getting the dataClient object was simplified. Now we can get it directly from the context.core.elasticsearch in the request handler

Checklist

Use strikethroughs to remove checklist items you don't feel are applicable to this PR.

• This was checked for cross-browser compatibility, including a check against IE11
• Any text added follows EUI's writing guidelines, uses sentence case text and includes i18n support
• Documentation was added for features that require explanation or tutorials
• Unit or functional tests were updated or added to match the most common scenarios
• This was checked for keyboard-only and screenreader accessibility

For maintainers

• This was checked for breaking API changes and was labeled appropriately
• This includes a feature addition or change that requires a release note and was labeled appropriately

[elasticmachine]

Pinging @elastic/kibana-app-arch (Team:AppArch)

[lizozom]

LGTM once green

[alexwizp]

Pinging @elastic/kibana-platform

[alexwizp]

@elasticmachine merge upstream

[elasticmachine]

💚 Build Succeeded

• continuous-integration/kibana-ci/pull-request
• Commit: d4f305a

History

• 💚 Build #16373 succeeded 0567854
• 💔 Build #16363 failed c924cdb

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@elasticmachine merge upstream