private static String getRegisteredServiceJwtSigningSecret(final RegisteredService registeredService) {
        return getRegisteredServiceJwtProperty(registeredService, RegisteredServiceProperties.TOKEN_SECRET_SIGNING);
    }
Create a JWT authenticator.

@return the jwt authenticator
support/cas-server-support-token-authentication/src/main/java/org/apereo/cas/token/authentication/TokenAuthenticationSecurity.java