[SECURITY SOLUTION] add enableExperimental plugin configuration setting

[paul-tavares]

Summary

Adds a new config setting to the security solution plugin (xpack.securitySolution.enableExperimental) that allows for string values to be defined, which are then used to expose experimental type of features. The value for this new configuration setting must be defined internally in the code, thus only a known set will be accepted.

This new setting will also be exposed to our cloud environments.

Current use case is to use it in preparation for integration with fleet-server (need to ensure existing integration env. continue to work) as well as hiding a feature that has been pulled from v7.13.

For Endpoint Artifact Manifest, it will use Fleet Server relative URLs when fleetServerEnabled is defined via xpack.securitySolution.enableExperimental:

[elasticmachine]

Pinging @elastic/security-onboarding-and-lifecycle-mgt (Team:Onboarding and Lifecycle Mgt)

[pzl]

👌

[kibanamachine]

💛 Build succeeded, but was flaky

• continuous-integration/kibana-ci/pull-request

• Commit: af4a488

• Storybooks Preview

• Flaky suites:

  • xpack-securitySolutionCypressChrome

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Test Failures

Kibana Pipeline / general / "before all" hook for "should contain notes".Timeline notes tab "before all" hook for "should contain notes"

Link to Jenkins

Stack Trace

Failed Tests Reporter:
  - Test has not failed recently on tracked branches

AssertionError: Timed out retrying after 60000ms: Expected to find element: `[data-test-subj="title-b51de5c0-8b1d-11eb-ab4a-01cdbfb76602"]`, but never found it.

Because this error occurred during a `before all` hook we are skipping the remaining tests in the current suite: `Timeline notes tab`

Although you have test retries enabled, we do not retry tests when `before all` or `after all` hooks fail
    at Object.openTimelineById (http://localhost:61181/__cypress/tests?p=cypress/integration/timelines/notes_tab.spec.ts:16023:15)
    at Context.eval (http://localhost:61181/__cypress/tests?p=cypress/integration/timelines/notes_tab.spec.ts:15041:24)

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Kibana Pipeline / general / "after all" hook for "should contain notes".Timeline notes tab "after all" hook for "should contain notes"

Link to Jenkins

Stack Trace

Failed Tests Reporter:
  - Test has not failed recently on tracked branches

CypressError: `cy.filter()` failed because it requires a DOM element.

The subject received was:

  > `undefined`

The previous command that ran was:

  > `cy.get()`

All 2 subject validations failed on this subject.

Because this error occurred during a `after all` hook we are skipping the remaining tests in the current suite: `Timeline notes tab`

Although you have test retries enabled, we do not retry tests when `before all` or `after all` hooks fail
    at ensureElement (http://elastic:changeme@localhost:61181/__cypress/runner/cypress_runner.js:161322:24)
    at validateType (http://elastic:changeme@localhost:61181/__cypress/runner/cypress_runner.js:161159:16)
    at Object.ensureSubjectByType (http://elastic:changeme@localhost:61181/__cypress/runner/cypress_runner.js:161195:9)
    at pushSubjectAndValidate (http://elastic:changeme@localhost:61181/__cypress/runner/cypress_runner.js:169888:15)
    at Context.<anonymous> (http://elastic:changeme@localhost:61181/__cypress/runner/cypress_runner.js:170225:18)
From Your Spec Code:
    at Object.closeTimeline (http://localhost:61181/__cypress/tests?p=cypress/integration/timelines/notes_tab.spec.ts:15976:43)
    at Context.eval (http://localhost:61181/__cypress/tests?p=cypress/integration/timelines/notes_tab.spec.ts:15051:20)

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Metrics [docs]

✅ unchanged

History

• 💔 Build #114125 failed 58af8cc
• 💔 Build #114033 failed 775e7fc

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

cc @paul-tavares