[php-src] Issue #9669: The help document of phpdbg misses an option

Issue: https://github.com/php/php-src/issues/9669 Author: ccccmd The "-h" option of phpdbg misses an option "z". + For the option "z", the following code appears during option parsing and modifies the zend_extensions_len and zend_extensions in sapi/phpdbg/phpdbg.c:1437-1443 for version 8.0.23. ``` case 'z': zend_extensions_len++; if (zend_extensions) { zend_extensions = realloc(zend_extensions, sizeof(char*) * zend_extensions_len); } else zend_extensions = malloc(sizeof(char*) * zend_extensions_len); zend_extensions[zend_extensions_len-1] = strdup(php_optarg); break; ``` But it does not appear in the document provided by "-h". It may prevent users from using the relevant function.