chore(deps): update actions/checkout action to v4 (#25)

This PR contains the following updates:

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

---

### Release Notes

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

###
[`v4`](https://redirect.github.com/actions/checkout/blob/HEAD/CHANGELOG.md#v422)

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

- `url-helper.ts` now leverages well-known environment variables by
[@&#8203;jww3](https://redirect.github.com/jww3) in
[https://github.com/actions/checkout/pull/1941](https://redirect.github.com/actions/checkout/pull/1941)
- Expand unit test coverage for `isGhes` by
[@&#8203;jww3](https://redirect.github.com/jww3) in
[https://github.com/actions/checkout/pull/1946](https://redirect.github.com/actions/checkout/pull/1946)

</details>

---

### Configuration

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Automerge - At any time (no schedule defined).

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

♻ **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
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---

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Author: scotwells

.github/workflows/build.yaml

@@ -26,7 +26,7 @@ jobs:
 
     steps:
     - name: Checkout repository
-      uses: actions/checkout@v3
+      uses: actions/checkout@v4
 
     - name: Log in to GitHub Container Registry
       uses: docker/login-action@v3.3.0