Update actions/checkout action to v4

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This PR contains the following updates:

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

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### Release Notes

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

### [`v4`](https://togithub.com/actions/checkout/blob/HEAD/CHANGELOG.md#v400)

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

-   [Support fetching without the --progress option](https://togithub.com/actions/checkout/pull/1067)
-   [Update to node20](https://togithub.com/actions/checkout/pull/1436)

</details>

---

### Configuration

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♻ **Rebasing**: Whenever PR becomes conflicted, 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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Author: renovate[bot]

.github/workflows/ci.yml

@@ -35,7 +35,7 @@ jobs:
 
     steps:
       - name: Check out code
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
       - name: Install Chef
         uses: actionshub/chef-install@2.0.4
       - name: Dokken

.github/workflows/md-links.yml

@@ -11,7 +11,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Check out code
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
       - name: markdown-link-check
         uses: gaurav-nelson/github-action-markdown-link-check@v1
         with: