[Entity Analytics] Add return types to all our routes

[hop-dev]

Summary

Add return types to all of our route handlers.

Before we did things like this in some APIs:

const resBody: CreateAssetCriticalityRecordResponse = { blah : 'blah'};

And I have moved to this style:

      async (
        context,
        request,
        response
      ): Promise<IKibanaResponse<CreateAssetCriticalityRecordResponse>> => {

This keeps the API docs in sync, I saw that this is how they do it in the elastic assistant plugin and liked it. I think it is clearer to have this stuff in the route definition, near the URL and request validation.

[elasticmachine]

Pinging @elastic/security-entity-analytics (Team:Entity Analytics)

[hop-dev]

/ci

[hop-dev]

@elasticmachine merge upstream

[kibana-ci]

💛 Build succeeded, but was flaky

• Buildkite Build
• Commit: 4ef6fc3

Failed CI Steps

• FTR Configs #57
• FTR Configs #72

Test Failures

• [job] [logs] FTR Configs #57 / dashboard sample data dashboard "before all" hook for "should launch sample flights data set dashboard"

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
securitySolution	20.5MB	20.5MB	+431.0B

History

• 💔 Build #225510 failed fdb9c78

To update your PR or re-run it, just comment with:
@elasticmachine merge upstream

cc @hop-dev

[tiansivive]

LGTM, just a small question