[Cases] Case templates configure api

[js-jankisalvi]

Summary

Implements #181573

This PR allows users to create, update and delete templates using existing configure API

Flaky test runner: https://buildkite.com/elastic/kibana-flaky-test-suite-runner/builds/5846

Test via Postman:

• Can create the template
• Can update the template
• Can delete the template
• Maximum 10 templates allowed
• Template cases fields are validated as per the existing schema
  • custom fields within templates are validated as per the existing schema

Checklist

• Unit or functional tests were updated or added to match the most common scenarios
• Flaky Test Runner was used on any tests changed

[elasticmachine]

Pinging @elastic/response-ops (Team:ResponseOps)

[elasticmachine]

Pinging @elastic/response-ops-cases (Feature:Cases)

[js-jankisalvi]

@elasticmachine merge upstream

[cnasikas]

Great PR! Great code coverage!!

[cnasikas]

Do we need to first check if there are assignees before notifying? Also, should we notify once outside the loop? Example:

const hasAssigneesInTemplate = templates.some((template) => Boolean(template.caseFields?.assignees && template.caseFields?.assignees.length > 0))

if (hasAssigneesInTemplate && !hasPlatinumLicenseOrGreater) {
        throw Boom.forbidden(
          'In order to assign users to cases, you must be subscribed to an Elastic Platinum license'
        );
      }

if (hasAssigneesInTemplate) {
 licensingService.notifyUsage(LICENSING_CASE_ASSIGNMENT_FEATURE);
}

templates.forEach((template, index) => { /// the validation }

[js-jankisalvi]

Updated in d9bcdbc

No need of forEach loop anymore

[kibana-ci]

💚 Build Succeeded

• Buildkite Build
• Commit: d9bcdbc

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
cases	479.3KB	479.3KB	+37.0B

Page load bundle

Size of the bundles that are downloaded on every page load. Target size is below 100kb

id	before	after	diff
cases	150.9KB	151.7KB	+822.0B

History

• 💔 Build #209465 failed e3775af
• 💔 Build #209409 failed e4d374a

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

cc @js-jankisalvi