[Synthetics] Migrate obs security api_keys FTR test to Scout API

[shahzad31]

Summary

Migrates the standalone observability api_integration/apis/security FTR test
(API key creation) into the Synthetics Scout API suite and removes the legacy
FTR config.

The single test verified that a privileged user can create an API key via
POST /internal/security/api_key with role descriptors carrying the
synthetics-service Elasticsearch privileges plus the legacy uptime feature.

Changes

• Add x-pack/solutions/observability/plugins/synthetics/test/scout/api/tests/api_keys.spec.ts.
  Uses the same cookie-based admin auth pattern as synthetics_enablement.spec.ts
  (samlAuth.asInteractiveUser('admin') + KIBANA_HEADERS), asserts 200 and
  name: 'test_api_key'.
• Delete x-pack/solutions/observability/test/api_integration/apis/security/
  (config.ts, index.ts, api_keys.ts).
• Remove the config from .buildkite/ftr-manifests/ftr_oblt_stateful_configs.yml
  and the stale .github/CODEOWNERS entry.
• Regenerate the Synthetics Scout .meta/api/standard.json.

Notes

• The synthetics-service ES privileges and '*' (all spaces) are inlined in the
  spec rather than imported from @kbn/synthetics-plugin/server/..., following
  this suite's local-constants convention (see fixtures/constants.ts) of not
  importing across the plugin server boundary.
• Tagged @local-stateful-classic only (not serverless) to preserve the original
  FTR scope — the legacy uptime feature and the stateful-only read_ilm cluster
  privilege are not meaningful in the serverless observability target.

Test plan

• node scripts/eslint --fix on the new spec — clean.
• Ran the new spec against a local stateful Scout server — 1 passed.
• CI green.

Made with Cursor

[infra-vault-gh-plugin-prod]

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