Update codecov/codecov-action action to v6 (#7561)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
|
[codecov/codecov-action](https://redirect.github.com/codecov/codecov-action)
| action | major | `v5` → `v6` |

---

> [!WARNING]
> Some dependencies could not be looked up. Check the [Dependency
Dashboard](../issues/357) for more information.

---

### Release Notes

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

###
[`v6`](https://redirect.github.com/codecov/codecov-action/compare/v5...v6)

[Compare
Source](https://redirect.github.com/codecov/codecov-action/compare/v5...v6)

</details>

---

### Configuration

📅 **Schedule**: (UTC)

- Branch creation
  - Between 12:00 AM and 03:59 AM, only on Monday (`* 0-3 * * 1`)
- 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/vortex-data/vortex).

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.github/workflows/rust-instrumented.yml

@@ -63,7 +63,7 @@ jobs:
             --ignore benchmarks/* --ignore 'vortex-test/*' \
             -o ${{ env.GRCOV_OUTPUT_FILE }}
       - name: Codecov
-        uses: codecov/codecov-action@v5
+        uses: codecov/codecov-action@v6
         with:
           name: run-${{ matrix.suite }}
           files: ${{ env.GRCOV_OUTPUT_FILE }}