Update actions/checkout action to v4.2.1

[renovate[bot]]

This PR contains the following updates:

Package	Type	Update	Change
actions/checkout	action	minor	v4.1.7 -> v4.2.1

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Release Notes

actions/checkout (actions/checkout)

### [`v4.2.1`](https://redirect.github.com/actions/checkout/blob/HEAD/CHANGELOG.md#v421) [Compare Source](https://redirect.github.com/actions/checkout/compare/v4.2.0...v4.2.1) - Check out other refs/\* by commit if provided, fall back to ref by [@​orhantoy](https://redirect.github.com/orhantoy) in [https://github.com/actions/checkout/pull/1924](https://redirect.github.com/actions/checkout/pull/1924) ### [`v4.2.0`](https://redirect.github.com/actions/checkout/blob/HEAD/CHANGELOG.md#v420) [Compare Source](https://redirect.github.com/actions/checkout/compare/v4.1.7...v4.2.0) - Add Ref and Commit outputs by [@​lucacome](https://redirect.github.com/lucacome) in [https://github.com/actions/checkout/pull/1180](https://redirect.github.com/actions/checkout/pull/1180) - Dependency updates by [@​dependabot-](https://redirect.github.com/dependabot-) [https://github.com/actions/checkout/pull/1777](https://redirect.github.com/actions/checkout/pull/1777), [https://github.com/actions/checkout/pull/1872](https://redirect.github.com/actions/checkout/pull/1872)

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