So far a CAPTCHA was not recognized in the response of the qwant engine and a
SearxEngineAPIException was raised by mistake. With this patch a CAPTCHA
redirect is recognized and the correct SearxEngineCaptchaException is raised.
Closes: https://github.com/searxng/searxng/issues/3806
Signed-off-by: Markus <markus@venom.fritz.box>