public IActionResult Index()
        {
            var googleState    = SetNewSessionState(_googleSessionSettings.StateKey);
            var redirectUri    = ApiUri.GetGoogleRedirectUri(HttpContext);
            var googleLoginUrl = _googleService.GetLoginUrl(googleState, redirectUri);

            var githubState    = SetNewSessionState(_githubSessionSettings.StateKey);
            var githubOAuthUrl = _githubService.GetOAuthCodeUrl(githubState);

            var viewModel = new IndexViewModel
            {
                GoogleLoginUrl = googleLoginUrl,
                GithubOAuthUrl = githubOAuthUrl
            };

            return(View(viewModel));
        }