Update actions/checkout action to v3.1.0

[renovate-bot]

This PR contains the following updates:

Package	Type	Update	Change
actions/checkout	action	minor	v3.0.2 -> v3.1.0

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Release Notes

actions/checkout

### [`v3.1.0`](https://togithub.com/actions/checkout/blob/HEAD/CHANGELOG.md#v310) [Compare Source](https://togithub.com/actions/checkout/compare/v3.0.2...v3.1.0) - [Use @​actions/core `saveState` and `getState`](https://togithub.com/actions/checkout/pull/939) - [Add `github-server-url` input](https://togithub.com/actions/checkout/pull/922)

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Configuration

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