docs: private static void checkValidAlternative(List<ClientConfig> alternativeClientConfigs) {
          if (alternativeClientConfigs.isEmpty()) {
              throw new InvalidConfigurationException("ClientFailoverConfig should have at least one client config.");
          }
          ClientConfig mainConfig = alternativeClientConfigs.get(0);
          for (ClientConfig alternativeClientConfig : alternativeClientConfigs.subList(1, alternativeClientConfigs.size())) {
              checkValidAlternative(mainConfig, alternativeClientConfig);
          }
  
      }