[8.12] Reverts erroneous addition of security plugin enabled config option (#175565)

[kibanamachine]

Backport

This will backport the following commits from main to 8.12:

• Reverts erroneous addition of security plugin enabled config option (#175565)

Questions ?

Please refer to the Backport tool documentation

[kibana-ci]

💛 Build succeeded, but was flaky

• Buildkite Build
• Commit: debc6d4

Failed CI Steps

• Defend Workflows Cypress Tests #7

Test Failures

• [job] [logs] Defend Workflows Cypress Tests #7 / Response console Processes operations: "after all" hook for ""processes" - should obtain a list of processes" "after all" hook for ""processes" - should obtain a list of processes"
• [job] [logs] Defend Workflows Cypress Tests #7 / Response console Processes operations: "before all" hook for ""processes" - should obtain a list of processes" "before all" hook for ""processes" - should obtain a list of processes"

Metrics [docs]

✅ unchanged

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

cc @jeramysoucy