[php-src] Issue #11568: ini setting zend.assertions should changeable PHP_INI_PERDIR without restriction

Issue: https://github.com/php/php-src/issues/11568 Author: claudepache ### Description Currently, if the ini setting zend.assertions is set to -1 in php.ini, it cannot be set to a different value in per-directory configuration file (PHP_INI_PERDIR) .user.ini or .htaccess (and vice versa). I want to be able to change zend.assertions PHP_INI_PERDIR without restriction, for the following reasons: 1. I have not always write access to php.ini; 2. I don’t know the PHP_INI_PERDIR equivalent of <?php if (ini_get('zend.assertions) !== '-1') ini_set('zend.assertions', '1'); ?> in order to avoid an E_WARNING. (Note that there is at least one other ini setting, namely short_open_tag, that also modify the result of compilation, but that is nevertheless changeable PHP_INI_PERDIR; from which I infer that my request is not unreasonable.)