chore(deps): update devdependency @antfu/eslint-config to ^2.21.0

[hywax-assistant]

This PR contains the following updates:

Package	Type	Update	Change
@antfu/eslint-config	devDependencies	minor	^2.20.0 -> ^2.21.0

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Release Notes

antfu/eslint-config (@​antfu/eslint-config)

### [`v2.21.0`](https://togithub.com/antfu/eslint-config/releases/tag/v2.21.0) [Compare Source](https://togithub.com/antfu/eslint-config/compare/v2.20.0...v2.21.0) #####    🐞 Bug Fixes - Only enable ts rules for ts files, fix [#​498](https://togithub.com/antfu/eslint-config/issues/498)  -  by [@​antfu](https://togithub.com/antfu) in [https://github.com/antfu/eslint-config/issues/498](https://togithub.com/antfu/eslint-config/issues/498) [(87142)](https://togithub.com/antfu/eslint-config/commit/87142e1) - Include `.d.mts` and `.d.cts`  -  by [@​antfu](https://togithub.com/antfu) [(0582c)](https://togithub.com/antfu/eslint-config/commit/0582c44) - Disbale type-aware in astro, handle formatter overrides with stylistic  -  by [@​tinchoz49](https://togithub.com/tinchoz49) and [@​antfu](https://togithub.com/antfu) in [https://github.com/antfu/eslint-config/issues/493](https://togithub.com/antfu/eslint-config/issues/493) [(e3230)](https://togithub.com/antfu/eslint-config/commit/e32301a) - Include `.jsx` files when the options set to true  -  by [@​antfu](https://togithub.com/antfu) [(96aff)](https://togithub.com/antfu/eslint-config/commit/96affbf) #####     [View changes on GitHub](https://togithub.com/antfu/eslint-config/compare/v2.20.0...v2.21.0)

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Configuration

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