text: Title: Cleanup alerting RBAC exception code
  Body: We've introduced some RBAC exemptions in PR https://github.com/elastic/kibana/pull/75563 and https://github.com/elastic/kibana/pull/77598 to avoid delivering breaking changes in a minor. We should deprecate this code and remove it when telemetry from https://github.com/elastic/kibana/issues/108716 shows usage is below 1% or deprecated for > 2.5 years.