Build(deps): Bump twig/markdown-extra from 3.13.0 to 3.15.0

Bumps [twig/markdown-extra](https://github.com/twigphp/markdown-extra) from 3.13.0 to 3.15.0.
- [Commits](twigphp/markdown-extra@v3.13.0...v3.15.0)

---
updated-dependencies:
- dependency-name: twig/markdown-extra
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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