[RENOVATE] Update actions/checkout action to v4 (#3)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| [actions/checkout](https://github.com/actions/checkout) | action | major | `v3` -> `v4` |

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### Release Notes

<details>
<summary>actions/checkout (actions/checkout)</summary>

### [`v4`](https://github.com/actions/checkout/blob/HEAD/CHANGELOG.md#v417)

[Compare Source](https://github.com/actions/checkout/compare/v3...v4)

-   Bump the minor-npm-dependencies group across 1 directory with 4 updates by [@&#8203;dependabot](https://github.com/dependabot) in https://github.com/actions/checkout/pull/1739
-   Bump actions/checkout from 3 to 4 by [@&#8203;dependabot](https://github.com/dependabot) in https://github.com/actions/checkout/pull/1697
-   Check out other refs/\* by commit by [@&#8203;orhantoy](https://github.com/orhantoy) in https://github.com/actions/checkout/pull/1774
-   Pin actions/checkout's own workflows to a known, good, stable version. by [@&#8203;jww3](https://github.com/jww3) in https://github.com/actions/checkout/pull/1776

</details>

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### Configuration

📅 **Schedule**: Branch creation - At any time (no schedule defined), Automerge - At any time (no schedule defined).

🚦 **Automerge**: Disabled by config. Please merge this manually once you are satisfied.

♻ **Rebasing**: Whenever PR is behind base branch, or you tick the rebase/retry checkbox.

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

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 - [ ] <!-- rebase-check -->If you want to rebase/retry this PR, check this box

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Reviewed-on: #3
Co-authored-by: Renovate <renovate@kjan.de>
Co-committed-by: Renovate <renovate@kjan.de>

.gitea/workflows/build.yaml

@@ -21,7 +21,7 @@ jobs:
             zip          
 
       - name: Checkout
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
 
       - name: Hash west modules
         id: hash-west