[php-src] PR #24612: ext/session: disable session.upload_progress.enabled by default

Pull Request: https://github.com/php/php-src/pull/24612 Author: jorgsowa Given today's security advisory I suggest including change of default of session.upload_progress.enabled to Off for PHP 8.6. It requires consensus of Security Team and PHP 8.6 Release Managers. It's follow-up of accepted RFC for other session defaults for 8.6 https://wiki.php.net/rfc/session_security_defaults I wanted to raise it after release along with other insecure defaults for next PHP version, but given the pace of development of AI, I think it may be considered to include it now. I will write topic on internals with more rationale.