Remove session.save_handler from php settings (#2784)
Remove session.save_handler from php settings (#2784)

This has never been required in PHP 5.6 and causes a fatal crash with PHP 7.2

Fixes #2783

Picked from 248a883
bauhouse/sym-todo-list,symphonycms/symphony-2,michael-e/symphony-2,bauhouse/sym-todo-list,michael-e/symphony-2,symphonycms/symphony-2