private async Task <HttpClient> GetAuthorizedHttpClientAsync()
        {
            var httpClient = _httpClientFactory();

            if (OAuthSpecified())
            {
                var accessToken = await _accessTokenProvider.GetAsync();

                httpClient.DefaultRequestHeaders.Authorization =
                    new AuthenticationHeaderValue("Bearer", accessToken);
            }
            else
            {
                SetUsernameAndPasswordAuthorization(httpClient);
            }
            return(httpClient);
        }