chore(deps): update actions/setup-python action to v6 (#480)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
|
[actions/setup-python](https://redirect.github.com/actions/setup-python)
| action | major | `v5` -> `v6` |

---

### Release Notes

<details>
<summary>actions/setup-python (actions/setup-python)</summary>

###
[`v6`](https://redirect.github.com/actions/setup-python/compare/v5...v6)

[Compare
Source](https://redirect.github.com/actions/setup-python/compare/v5...v6)

</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 is behind base branch, 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/check-test-release.yml

@@ -33,7 +33,7 @@ jobs:
       with:
         fetch-depth: 0
 
-    - uses: actions/setup-python@v5
+    - uses: actions/setup-python@v6
       with:
         python-version: ${{ matrix.python }}
         cache: 'pip'
@@ -62,7 +62,7 @@ jobs:
     - uses: actions/checkout@v5
       with:
         fetch-depth: 0
-    - uses: actions/setup-python@v5
+    - uses: actions/setup-python@v6
       with:
         python-version: '3.13'