chore: 🤖 update dependency knip to v5.21.0

[renovate[bot]]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
knip (source)	5.20.0 -> 5.21.0

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Release Notes

webpro-nl/knip (knip)

### [`v5.21.0`](https://togithub.com/webpro-nl/knip/releases/tag/5.21.0) [Compare Source](https://togithub.com/webpro-nl/knip/compare/5.20.0...5.21.0) - Add webdriver-io plugin ([`7414dc1`](https://togithub.com/webpro-nl/knip/commit/7414dc1a)) - Update plugin docs ([`df35b9f`](https://togithub.com/webpro-nl/knip/commit/df35b9f4)) - Minor housekeeping ([`1422c9d`](https://togithub.com/webpro-nl/knip/commit/1422c9d2)) - Add size-limit plugin ([`dbd82f8`](https://togithub.com/webpro-nl/knip/commit/dbd82f87)) - Add lockfile-lint plugin ([`d70d0de`](https://togithub.com/webpro-nl/knip/commit/d70d0de7)) - Use provided name in plugin template ([`43961f9`](https://togithub.com/webpro-nl/knip/commit/43961f91)) - Minor housekeeping ([`c81b1a2`](https://togithub.com/webpro-nl/knip/commit/c81b1a23)) - Update readme with badges and stuff ([`c18fcba`](https://togithub.com/webpro-nl/knip/commit/c18fcba5)) - Update docs (Configuring Project Files) ([`e10ac2e`](https://togithub.com/webpro-nl/knip/commit/e10ac2e4))

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Configuration

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🚦 Automerge: Enabled.

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🔕 Ignore: Close this PR and you won't be reminded about this update again.

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