Update codecov/codecov-action action to v5 (#186)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
|
[codecov/codecov-action](https://redirect.github.com/codecov/codecov-action)
| action | major | `v4` -> `v5` |

---

### Release Notes

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

###
[`v5`](https://redirect.github.com/codecov/codecov-action/blob/HEAD/CHANGELOG.md#v507)

[Compare
Source](https://redirect.github.com/codecov/codecov-action/compare/v4...v5)

##### What's Changed

- fix: use HEAD_REPO by
[@&#8203;thomasrockhu-codecov](https://redirect.github.com/thomasrockhu-codecov)
in
[https://github.com/codecov/codecov-action/pull/1690](https://redirect.github.com/codecov/codecov-action/pull/1690)

**Full Changelog**:
https://github.com/codecov/codecov-action/compare/v5.0.6..v5.0.7

</details>

---

### Configuration

📅 **Schedule**: Branch creation - "after 1am and before 3am every
weekday" in timezone Etc/UTC, 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

---

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.github/workflows/ci.yaml

@@ -42,7 +42,7 @@ jobs:
       - name: Run tests
         run: tox run -e unit
       - name: Upload Coverage to Codecov
-        uses: codecov/codecov-action@v4
+        uses: codecov/codecov-action@v5
 
   lib-check:
     name: Check libraries