code: private String createServiceCredentials(AuthleteConfiguration configuration)
      {
          if (configuration.getServiceAccessToken() != null)
          {
              return "Bearer " + configuration.getServiceAccessToken();
          }
          else
          {
              String key    = configuration.getServiceApiKey();
              String secret = configuration.getServiceApiSecret();
  
              return new BasicCredentials(key, secret).format();
          }
      }
docs: Create an authorization header for the service.