feat: Token Revocation, Request Object and OP Certification (#130)

FEATURES (and FIXES):
- support OAuth 2.0 Token Revocation [RFC 7009](https://datatracker.ietf.org/doc/html/rfc7009)
- handle request object using `request` parameter [OIDC Core 1.0 Request Object](https://openid.net/specs/openid-connect-core-1_0.html#RequestObject)
- handle response mode
- added some information to the discovery endpoint:
  - revocation_endpoint (added with token revocation) 
  - revocation_endpoint_auth_methods_supported (added with token revocation)
  - revocation_endpoint_auth_signing_alg_values_supported (added with token revocation)
  - token_endpoint_auth_signing_alg_values_supported (was missing)
  - introspection_endpoint_auth_signing_alg_values_supported (was missing)
  - request_object_signing_alg_values_supported (added with request object)
  - request_parameter_supported (added with request object)
 - fixed `removeUserinfoScopes ` now returns the scopes without "userinfo" scopes (profile, email, phone, addedd) [source diff](https://github.com/caos/oidc/pull/130/files#diff-fad50c8c0f065d4dbc49d6c6a38f09c992c8f5d651a479ba00e31b500543559eL170-R171)
- improved error handling (pkg/oidc/error.go) and fixed some wrong OAuth errors (e.g. `invalid_grant` instead of `invalid_request`)
- improved MarshalJSON and added MarshalJSONWithStatus
- removed deprecated PEM decryption from `BytesToPrivateKey`  [source diff](https://github.com/caos/oidc/pull/130/files#diff-fe246e428e399ccff599627c71764de51387b60b4df84c67de3febd0954e859bL11-L19)
- NewAccessTokenVerifier now uses correct (internal) `accessTokenVerifier` [source diff](https://github.com/caos/oidc/pull/130/files#diff-3a01c7500ead8f35448456ef231c7c22f8d291710936cac91de5edeef52ffc72L52-R52)

BREAKING CHANGE:
- move functions from `utils` package into separate packages
- added various methods to the (OP) `Configuration` interface [source diff](https://github.com/caos/oidc/pull/130/files#diff-2538e0dfc772fdc37f057aecd6fcc2943f516c24e8be794cce0e368a26d20a82R19-R32)
- added revocationEndpoint to `WithCustomEndpoints ` [source diff](https://github.com/caos/oidc/pull/130/files#diff-19ae13a743eb7cebbb96492798b1bec556673eb6236b1387e38d722900bae1c3L355-R391)
- remove unnecessary context parameter from JWTProfileExchange [source diff](https://github.com/caos/oidc/pull/130/files#diff-4ed8f6affa4a9631fa8a034b3d5752fbb6a819107141aae00029014e950f7b4cL14)

example/internal/mock/storage.go

@@ -32,6 +32,7 @@ func NewAuthStorage() op.Storage {
 type AuthRequest struct {
 	ID            string
 	ResponseType  oidc.ResponseType
+	ResponseMode  oidc.ResponseMode
 	RedirectURI   string
 	Nonce         string
 	ClientID      string
@@ -88,6 +89,10 @@ func (a *AuthRequest) GetResponseType() oidc.ResponseType {
 	return a.ResponseType
 }
 
+func (a *AuthRequest) GetResponseMode() oidc.ResponseMode {
+	return a.ResponseMode
+}
+
 func (a *AuthRequest) GetScopes() []string {
 	return []string{
 		"openid",
@@ -170,6 +175,11 @@ func (s *AuthStorage) TokenRequestByRefreshToken(ctx context.Context, refreshTok
 func (s *AuthStorage) TerminateSession(_ context.Context, userID, clientID string) error {
 	return nil
 }
+
+func (s *AuthStorage) RevokeToken(ctx context.Context, token string, userID string, clientID string) *oidc.Error {
+	return nil
+}
+
 func (s *AuthStorage) GetSigningKey(_ context.Context, keyCh chan<- jose.SigningKey) {
 	keyCh <- jose.SigningKey{Algorithm: jose.RS256, Key: s.key}
 }
@@ -289,7 +299,7 @@ func (c *ConfClient) AuthMethod() oidc.AuthMethod {
 }
 
 func (c *ConfClient) IDTokenLifetime() time.Duration {
-	return time.Duration(5 * time.Minute)
+	return 5 * time.Minute
 }
 func (c *ConfClient) AccessTokenType() op.AccessTokenType {
 	return c.accessTokenType