code: @Reference(policy = ReferencePolicy.DYNAMIC, cardinality = ReferenceCardinality.MULTIPLE)
      protected Map<String, Object> setConfiguration(ServiceReference<SecurityConfiguration> ref) {
          String id = (String) ref.getProperty(KEY_ID);
          if (id != null) {
              configs.putReference(id, ref);
          } else {
              Tr.error(tc, "SECURITY_SERVICE_REQUIRED_SERVICE_WITHOUT_ID", "securityConfiguration");
          }
          return getServiceProperties();
      }
docs: Method will be called for each SecurityConfiguration that is registered
  in the OSGi service registry. We maintain an internal map of these for
  easy access.
  
  If the ID is not defined for the configuration, it is incomplete and
  can not be used.
  
  @param ref Reference to a registered SecurityConfiguration