Bump twig/twig from 2.15.3 to 2.16.1 in /generator (#516)

Bumps [twig/twig](https://github.com/twigphp/Twig) from 2.15.3 to 2.16.1.
- [Changelog](https://github.com/twigphp/Twig/blob/v2.16.1/CHANGELOG)
- [Commits](twigphp/Twig@v2.15.3...v2.16.1)

---
updated-dependencies:
- dependency-name: twig/twig
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>