public HMACAuthenticationHandler(IOptionsMonitor <HMACAuthenticationOptions> options,
                                  ILoggerFactory logger,
                                  UrlEncoder encoder,
                                  ISystemClock clock,
                                  ISecretLookup lookup)
     : base(options, logger, encoder, clock)
 {
     this.lookup = lookup ?? throw new ArgumentNullException(nameof(lookup));
 }