chore(deps): update dependency knip to v5.21.2 (#501)

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This PR contains the following updates:

| Package | Change | Age | Adoption | Passing | Confidence |
|---|---|---|---|---|---|
| [knip](https://knip.dev)
([source](https://togithub.com/webpro-nl/knip/tree/HEAD/packages/knip))
| [`5.21.1` ->
`5.21.2`](https://renovatebot.com/diffs/npm/knip/5.21.1/5.21.2) |
[![age](https://developer.mend.io/api/mc/badges/age/npm/knip/5.21.2?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![adoption](https://developer.mend.io/api/mc/badges/adoption/npm/knip/5.21.2?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![passing](https://developer.mend.io/api/mc/badges/compatibility/npm/knip/5.21.1/5.21.2?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![confidence](https://developer.mend.io/api/mc/badges/confidence/npm/knip/5.21.1/5.21.2?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|

---

### Release Notes

<details>
<summary>webpro-nl/knip (knip)</summary>

###
[`v5.21.2`](https://togithub.com/webpro-nl/knip/compare/5.21.1...bd77bcce5acfdd108ab54398c922eb03f07fc65f)

[Compare
Source](https://togithub.com/webpro-nl/knip/compare/5.21.1...5.21.2)

</details>

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