package/php: security bump version to 8.2.18
Fixes CVE-2024-1874, CVE-2024-2756 & CVE-2024-3096.
Changelog: https://www.php.net/ChangeLog-8.php#PHP_8_2
Release notes: https://news-web.php.net/php.announce/423
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>