upgrade: update actions/download-artifact action to v4.1.8 (#570)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
|
[actions/download-artifact](https://redirect.github.com/actions/download-artifact)
| action | patch | `v4.1.7` -> `v4.1.8` |

---

### Release Notes

<details>
<summary>actions/download-artifact (actions/download-artifact)</summary>

###
[`v4.1.8`](https://redirect.github.com/actions/download-artifact/releases/tag/v4.1.8)

[Compare
Source](https://redirect.github.com/actions/download-artifact/compare/v4.1.7...v4.1.8)

#### What's Changed

- Update
[@&#8203;actions/artifact](https://redirect.github.com/actions/artifact)
version, bump dependencies by
[@&#8203;robherley](https://redirect.github.com/robherley) in
[https://github.com/actions/download-artifact/pull/341](https://redirect.github.com/actions/download-artifact/pull/341)

**Full Changelog**:
actions/download-artifact@v4...v4.1.8

</details>

---

### Configuration

📅 **Schedule**: Branch creation - "every weekend" in timezone
Asia/Tokyo, 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.

---

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

---

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.github/workflows/release.yml

@@ -98,7 +98,7 @@ jobs:
     runs-on: ubuntu-latest
     needs: build
     steps:
-      - uses: actions/download-artifact@v4.1.7
+      - uses: actions/download-artifact@v4.1.8
         with:
           name: sha256