Cleanup items for new APIs:

ServiceMeshExtension should be in maistra.io group, not extensions.maistra.io

Move security.mtls.enabled and security.mtls.auto to security.dataPlane.mtls and security.dataPlane.autoMTLS.  This will better distinguish them from control plane settings (security.controlPlane.*)

Move prometheus.telemetry.metricsExpiryDuration up a level to prometheus.metricEpiryDuration.  This is only used with mixer (v1) and scrape is only used with istiod (v2).