Forum software updated

[Charlie]

The forum software has been updated to the latest version of phpBB; 3.3.11 "Bertie's trip to Zagreb". This version is a maintenance release of the 3.3.x branch which increases the minimum required PHP version, adds a new search index progress bar with added statistics, optimizes support for PHP 8.2, and adds further security hardening.

There are no obvious major enhancements to the front end from the users' perspective in this update other than better compatibility of the message editor in Safari. Under the skin it's a security and performance upgrade.