chore(deps): Update actions/upload-artifact action to v4 (#179)

This PR contains the following updates:

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

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### Release Notes

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

### [`v4`](https://togithub.com/actions/upload-artifact/compare/v3...v4)

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

</details>

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### Configuration

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Author: cq-bot

.github/workflows/unittest.yml

@@ -37,7 +37,7 @@ jobs:
       - name: Generate coverage report
         if: always() && matrix.os == 'ubuntu-latest'
         run: go tool cover -html coverage.out -o coverage.html
-      - uses: actions/upload-artifact@v3
+      - uses: actions/upload-artifact@v4
         if: always() && matrix.os == 'ubuntu-latest'
         with:
           name: Code coverage