chore(deps): update actions/checkout action to v3 (#395)

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This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| [actions/checkout](https://togithub.com/actions/checkout) | action | major | `v2` -> `v3` |

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### Release Notes

<details>
<summary>actions/checkout</summary>

### [`v3`](https://togithub.com/actions/checkout/compare/v2...v3)

[Compare Source](https://togithub.com/actions/checkout/compare/v2...v3)

</details>

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### Configuration

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Author: renovate-bot