private static void addErrorMessageToContext(final RequestContext requestContext) {
        WebUtils.addErrorMessageToContext(requestContext, CODE);
    }
This is {@link GoogleAuthenticatorValidateSelectedRegistrationAction}.

@author Misagh Moayyed
@since 6.3.0
support/cas-server-support-gauth-core/src/main/java/org/apereo/cas/gauth/web/flow/GoogleAuthenticatorValidateSelectedRegistrationAction.java