Upgrade FrankenPHP to v1.11.2

[jaydrogers]

Upgrades FrankenPHP to v1.11.2 which includes security updates, including one with HIGH severity:

🛡️ Security Fixes

• GHSA-g966-83w7-6w38: Path confusion via Unicode casing in CGI path splitting could allow execution of arbitrary files. Fixed by @AbdrrahimDahmani and @dunglas in commit 04fdc0c.
• GHSA-r3xh-3r3w-47gp: Fixed a session leak between requests handled by workers. Fixed by @xavierleune in commit 24d6c99.
• GHSA-x9p2-77v6-6vhf: Fixed delayed propagation of security fixes in upstream base Docker images. Fixed by @opctim in commit be2d6b9.
• Prevent potential cache pollution issues in CI builds by @dunglas in ci: disable Docker cache when building prod images php/frankenphp#2164