chore(deps): update dependency knip to v5.6.1 (#108)

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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/knip/tree/HEAD/packages/knip)) |
[`5.6.0` -> `5.6.1`](https://renovatebot.com/diffs/npm/knip/5.6.0/5.6.1)
|
[![age](https://developer.mend.io/api/mc/badges/age/npm/knip/5.6.1?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![adoption](https://developer.mend.io/api/mc/badges/adoption/npm/knip/5.6.1?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![passing](https://developer.mend.io/api/mc/badges/compatibility/npm/knip/5.6.0/5.6.1?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![confidence](https://developer.mend.io/api/mc/badges/confidence/npm/knip/5.6.0/5.6.1?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|

---

### Release Notes

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

### [`v5.6.1`](https://togithub.com/webpro/knip/releases/tag/5.6.1)

[Compare Source](https://togithub.com/webpro/knip/compare/5.6.0...5.6.1)

- Fix recursive tsconfig extends retrieval (resolves
[#&#8203;574](https://togithub.com/webpro/knip/issues/574))
([`78f6a78`](https://togithub.com/webpro/knip/commit/78f6a785))
- Don't return `null` for vitest environment (fixes
[#&#8203;575](https://togithub.com/webpro/knip/issues/575))
([`473d7ab`](https://togithub.com/webpro/knip/commit/473d7abb))

</details>

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