Upgrade twig/twig to 3.15.0

Problem/Motivation

There's new release which breaks lots of tests https://github.com/twigphp/Twig/blob/v3.15.0/CHANGELOG

Steps to reproduce

Upgrade and run tests

Proposed resolution

Upgrade and fix deprecations

- https://github.com/twigphp/Twig/pull/4335
- https://github.com/twigphp/Twig/pull/4398

Remaining tasks

- fix code and review
- commit

User interface changes

Introduced terminology

API changes

Data model changes

Release notes snippet