Bump shikiji from 0.6.12 to 0.6.13

Bumps [shikiji](https://github.com/antfu/shikiji/tree/HEAD/packages/shikiji) from 0.6.12 to 0.6.13.
- [Release notes](https://github.com/antfu/shikiji/releases)
- [Commits](https://github.com/antfu/shikiji/commits/v0.6.13/packages/shikiji)

---
updated-dependencies:
- dependency-name: shikiji
  dependency-type: direct:development
  update-type: version-update:semver-patch
...

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