Deprecated functions in CakePHP

[wsergent]

Updated code to CakePHP suggested alternatives to avoid Deprecation warnings

[wsergent]

Further, the documentation (https://captcha.com/doc/php/cakephp-captcha.html) needs to be updated (not in Repo):
$this->Form->input should be $this->Form->control

$isHuman = captcha_validate($this->request->data['CaptchaCode']); should now be $isHuman = captcha_validate($this->getRequest()->getData('CaptchaCode'));

unset($this->request->data['CaptchaCode']); needs to be updated. However, standard practice is not to unset getRequest() items - see this stackoverflow for more info: https://stackoverflow.com/questions/44993792/how-to-unset-request-data-in-cakephp-3-4
But, this could be replace with:

    $data = $this->getRequest()->getData();
    unset($data['CaptchaCode']);
    $this->request = $this->getRequest()->withParsedBody($data);