As we are rolling out the user profile feature, we'd like to expand the [Usage API](https://www.elastic.co/guide/en/elasticsearch/reference/current/usage-api.html) to report usage stats of user profiles such as (1) number of enabled user profiles and (2) number of user profiles that are [activated](https://www.elastic.co/guide/en/elasticsearch/reference/current/security-api-activate-user-profile.html) over the past X days. 

Response of the Usage API already contains a `security` field that groups relevant stats from security related features. We expect the new stats for user profiles should be added under it as well, for example:
```
{
  "security: {
    "user_profile": {
      "activated": 78,
      "recently_activated": 42  <1>
    }
  }
}
```
<1> The use of `recently_` is chosen to avoid the field to be tied to a specific time period so it is easier to evolve the definition in future.

x-pack/plugin/security/src/main/java/org/elasticsearch/xpack/security/Security.java
import org.elasticsearch.xpack.core.ssl.TransportTLSBootstrapCheck;
import org.elasticsearch.xpack.core.ssl.action.GetCertificateInfoAction;
import org.elasticsearch.xpack.core.ssl.action.TransportGetCertificateInfoAction;
import org.elasticsearch.xpack.core.ssl.rest.RestGetCertificateInfoAction;
import org.elasticsearch.xpack.security.action.TransportClearSecurityCacheAction;
import org.elasticsearch.xpack.security.action.TransportDelegatePkiAuthenticationAction;
import org.elasticsearch.xpack.security.action.apikey.TransportBulkUpdateApiKeyAction;
import org.elasticsearch.xpack.security.action.apikey.TransportCreateApiKeyAction;
import org.elasticsearch.xpack.security.action.apikey.TransportGetApiKeyAction;
import org.elasticsearch.xpack.security.action.apikey.TransportGrantApiKeyAction;
import org.elasticsearch.xpack.security.action.apikey.TransportInvalidateApiKeyAction;
import org.elasticsearch.xpack.security.action.apikey.TransportQueryApiKeyAction;
import org.elasticsearch.xpack.security.action.apikey.TransportUpdateApiKeyAction;
import org.elasticsearch.xpack.security.action.enrollment.TransportKibanaEnrollmentAction;
import org.elasticsearch.xpack.security.action.enrollment.TransportNodeEnrollmentAction;
import org.elasticsearch.xpack.security.action.filter.SecurityActionFilter;
import org.elasticsearch.xpack.security.action.oidc.TransportOpenIdConnectAuthenticateAction;
import org.elasticsearch.xpack.security.action.oidc.TransportOpenIdConnectLogoutAction;
import org.elasticsearch.xpack.security.action.oidc.TransportOpenIdConnectPrepareAuthenticationAction;
import org.elasticsearch.xpack.security.action.privilege.TransportClearPrivilegesCacheAction;
import org.elasticsearch.xpack.security.action.privilege.TransportDeletePrivilegesAction;
import org.elasticsearch.xpack.security.action.privilege.TransportGetBuiltinPrivilegesAction;
import org.elasticsearch.xpack.security.action.privilege.TransportGetPrivilegesAction;
import org.elasticsearch.xpack.security.action.privilege.TransportPutPrivilegesAction;
import org.elasticsearch.xpack.security.action.profile.TransportActivateProfileAction;
import org.elasticsearch.xpack.security.action.profile.TransportGetProfilesAction;
import org.elasticsearch.xpack.security.action.profile.TransportProfileHasPrivilegesAction;
import org.elasticsearch.xpack.security.action.profile.TransportSetProfileEnabledAction;
import org.elasticsearch.xpack.security.action.profile.TransportSuggestProfilesAction;
import org.elasticsearch.xpack.security.action.profile.TransportUpdateProfileDataAction;