Set Certificate Authority in Serverless FTR base config based on MKI

[jeramysoucy]

Summary

Follow-up to #165846

Moves the check for cloud/MKI to the base serverless FTR config. We found three use cases where the Kibana server configuration was providing a CA override:

1. In the serverless supertest
2. In the APM API supertest
3. In the FTR KIbana server's Kibana client instantiation

Locally, CA certs should be overridden to our self-singed certs, while on MKI we should default to the Mozilla well-known CAs. Moving the check to the test config (if it proves successful) handles all three cases without the need for adding environment variable checks in multiple places.

cc @kc13greiner

[kibana-ci]

💔 Build Failed

• Buildkite Build
• Commit: 75ad2cb
• Interpreting CI Failures

Failed CI Steps

• Serverless Security Cypress Tests #2
• Serverless Security Cypress Tests #6
• Serverless Security Cypress Tests #6
• Serverless Security Cypress Tests #10
• Serverless Security Cypress Tests #10
• Serverless Security Cypress Tests #11
• Serverless Security Cypress Tests #11
• Serverless Security Cypress Tests #12
• Serverless Security Cypress Tests #12
• Serverless Security Investigations Cypress Tests #1

Test Failures

• [job] [logs] Serverless Security Cypress Tests #2 / Prebuilt rules Alerts rules, prebuilt rules Rule monitoring table "before each" hook for "Allows to enable/disable all rules at once" "before each" hook for "Allows to enable/disable all rules at once"

Metrics [docs]

✅ unchanged

History

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@elasticmachine merge upstream

[dmlemeshko]

Tested locally for both functional & api integration tests against MKI. Thank you for the fixes!

[elasticmachine]

Pinging @elastic/kibana-security (Team:Security)