[Enterprise Search] Model state change error handling

[demjened]

Summary

This PR adds error handling to model actions (deploy, start) in the ML model selection list. If either of these API calls fail, an error is displayed. The error stays on the screen until the flyout is reopened or another model action succeeds.

Unfortunately there's no straightforward way to surface the root cause, so we display a generic error message to check the Kibana logs (which do contain the cause).

Checklist

• Any text added follows EUI's writing guidelines, uses sentence case text and includes i18n support
• Unit or functional tests were updated or added to match the most common scenarios
• Flaky Test Runner was used on any tests changed
• Any UI touched in this PR is usable by keyboard only (learn more about keyboard accessibility)
• Any UI touched in this PR does not create any new axe failures (run axe in browser: FF, Chrome)
• This renders correctly on smaller devices using a responsive layout. (You can test this in your browser)

[kibana-ci]

💚 Build Succeeded

• Buildkite Build
• Commit: 83d5df4

Metrics [docs]

Async chunks

Total size of all lazy-loaded chunks that will be downloaded as the user navigates the app

id	before	after	diff
enterpriseSearch	2.7MB	2.7MB	+525.0B

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@elasticmachine merge upstream