ClaimsSupported                  []string `json:"claims_supported,omitempty"`
	CodeChallengeMethodsSupported    []string `json:"code_challenge_methods_supported,omitempty"`
}

func parseDiscoveryDoc(ustr string) (DiscoveryDoc, error) {
	d := DiscoveryDoc{}
	req, err := http.NewRequest(http.MethodGet, ustr, nil)
	if err != nil {
		return d, err
	}
	clnt := http.Client{
		Transport: http.DefaultTransport,