[Event annotations] add more API integration tests

[drewdaemon]

Summary

Covers the event annotations API in tests.

Part of #159053
Part of #161038

[elasticmachine]

Pinging @elastic/kibana-visualizations (Team:Visualizations)

[stratoula]

Vis team changes LGTM, code review only. Have we run them on FR flaky server?

[drewdaemon]

Flaky test runner green for 100 runs: https://buildkite.com/elastic/kibana-flaky-test-suite-runner/builds/3161

[kibana-ci]

💚 Build Succeeded

• Buildkite Build
• Commit: 3bc1520

Metrics [docs]

Public APIs missing comments

Total count of every public API that lacks a comment. Target amount is 0. Run node scripts/build_api_docs --plugin [yourplugin] --stats comments for more detailed information.

id	before	after	diff
eventAnnotation	195	201	+6

Public APIs missing exports

Total count of every type that is part of your API that should be exported but is not. This will cause broken links in the API documentation system. Target amount is 0. Run node scripts/build_api_docs --plugin [yourplugin] --stats exports for more detailed information.

id	before	after	diff
eventAnnotation	5	6	+1

Unknown metric groups

API count

id	before	after	diff
eventAnnotation	195	201	+6

History

• 💚 Build #159123 succeeded 4e16251

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