ci: update codecov/codecov-action action to v5 (#518)

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#v511)

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

##### What's Changed

**Full Changelog**:
https://github.com/codecov/codecov-action/compare/v5.1.0..v5.1.1

</details>

---

### Configuration

📅 **Schedule**: Branch creation - "on the 1st day of the month" in
timezone Asia/Shanghai, 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.

👻 **Immortal**: This PR will be recreated if closed unmerged. Get
[config
help](https://redirect.github.com/renovatebot/renovate/discussions) if
that's undesired.

---

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

---

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.github/workflows/ci.yaml

@@ -71,7 +71,7 @@ jobs:
         env:
           TR_PROTOCOL: 'http+unix'
           TR_HOST: '/tmp/transmission.socket'
-      - uses: codecov/codecov-action@v4
+      - uses: codecov/codecov-action@v5
         with:
           flags: "unix-socket"
           token: ${{ secrets.CODECOV_TOKEN }}