chore(deps): update dependency shiki to v1.21.1

[renovate[bot]]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
shiki (source)	1.21.0 -> 1.21.1

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Release Notes

shikijs/shiki (shiki)

### [`v1.21.1`](https://redirect.github.com/shikijs/shiki/releases/tag/v1.21.1) [Compare Source](https://redirect.github.com/shikijs/shiki/compare/v1.21.0...v1.21.1) #####    🚀 Features - Update deps  -  by [@​antfu](https://redirect.github.com/antfu) [(2bdf1)](https://redirect.github.com/shikijs/shiki/commit/2bdf1b89) #####     [View changes on GitHub](https://redirect.github.com/shikijs/shiki/compare/v1.21.0...v1.21.1)

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Configuration

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