[Defend Workflows] Enable Artifacts cy tests against serverless

[gergoabraham]

Summary

Enables Artifact tabs in Policy details and Artifacts cypress tests against serverless. Or at least the test cases that has ALL privilege (or NONE for the Artifacts tests), because there are no such roles in serverless environment that have:

• read privilege for policy, but no privilege for artifacts,
• read privilege for artifacts

Additionally,

• @skipInServerless tag is added,
• the two tests use the usual indexEndpointHosts() to have mocked data,
• and the old loadEndpointDataForEventFiltersIfNeeded() is deleted

[elasticmachine]

Pinging @elastic/security-defend-workflows (Team:Defend Workflows)

[gergoabraham]

@elasticmachine merge upstream

[kibana-ci]

💚 Build Succeeded

• Buildkite Build
• Commit: 4a4476c

Metrics [docs]

✅ unchanged

History

• 💔 Build #174728 failed 64da556

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

cc @gergoabraham

[tomsonpl]

LGTM 👍 thanks for doing this :)