public SiteVerifierProxyTests()
        {
            var configurationRoot = new ConfigurationBuilder()
                                    .AddJsonFile("secrets.json")
                                    .Build();
            var recaptchaSettings = new RecaptchaSettings
            {
                SecretKey = configurationRoot["reCAPTCHATestSecretKey"]
            };

            _proxy = new SiteVerifierProxy(() => new HttpClient(), () => recaptchaSettings,
                                           JsonConvert.DeserializeObject);
        }
 public ValidateRecaptchaFilter(ISiteVerifier siteVerifier, ValidateRecaptchaFilterOptions options)
 {
     _siteVerifier = siteVerifier ?? throw new ArgumentNullException(nameof(siteVerifier));
     _options      = options ?? throw new ArgumentNullException(nameof(options));
 }