chore(deps): update codecov/codecov-action action to v5.5.2 (#4156)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| [codecov/codecov-action](https://redirect.github.com/codecov/codecov-action) | action | patch | `v5.5.1` -> `v5.5.2` |

---

### Release Notes

<details>
<summary>codecov/codecov-action (codecov/codecov-action)</summary>

### [`v5.5.2`](https://redirect.github.com/codecov/codecov-action/blob/HEAD/CHANGELOG.md#v552)

[Compare Source](https://redirect.github.com/codecov/codecov-action/compare/v5.5.1...v5.5.2)

##### What's Changed

**Full Changelog**: <https://github.com/codecov/codecov-action/compare/v5.5.1..v5.5.2>

</details>

---

### 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 becomes conflicted, 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

---

This PR was generated by [Mend Renovate](https://mend.io/renovate/). View the [repository job log](https://developer.mend.io/github/ObolNetwork/charon).
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Author: renovate[bot]

.github/workflows/unit-tests.yml

@@ -25,7 +25,7 @@ jobs:
             ${{ runner.os }}-go-
       - run: go test -coverprofile=coverage.out -covermode=atomic -timeout=10m -race ./...
       - name: Upload coverage to Codecov
-        uses: codecov/codecov-action@5a1091511ad55cbe89839c7260b706298ca349f7 # v5.5.1
+        uses: codecov/codecov-action@671740ac38dd9b0130fbe1cec585b89eea48d3de # v5.5.2
         with:
           token: ${{ secrets.CODECOV_TOKEN }}
           files: coverage.out