docs: public static ClientBuilder cluster() throws IOException {
      final ClientBuilder builder = new ClientBuilder();
  
      final String host = System.getenv(ENV_SERVICE_HOST);
      final String port = System.getenv(ENV_SERVICE_PORT);
      builder.setBasePath("https://" + host + ":" + port);
  
      final String token =
          new String(
              Files.readAllBytes(Paths.get(SERVICEACCOUNT_TOKEN_PATH)), Charset.defaultCharset());
      builder.setCertificateAuthority(Files.readAllBytes(Paths.get(SERVICEACCOUNT_CA_PATH)));
      builder.setAuthentication(new AccessTokenAuthentication(token));
  
      return builder;
    }