chore(deps): update dependency tox to v4.28.1 (#829)

This PR contains the following updates:

| Package | Change | Age | Confidence |
|---|---|---|---|
| [tox](https://redirect.github.com/tox-dev/tox)
([changelog](https://tox.wiki/en/latest/changelog.html)) | `==4.28.0` ->
`==4.28.1` |
[![age](https://developer.mend.io/api/mc/badges/age/pypi/tox/4.28.1?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![confidence](https://developer.mend.io/api/mc/badges/confidence/pypi/tox/4.28.0/4.28.1?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|

---

### Release Notes

<details>
<summary>tox-dev/tox (tox)</summary>

###
[`v4.28.1`](https://redirect.github.com/tox-dev/tox/compare/4.28.0...4.28.1)

[Compare
Source](https://redirect.github.com/tox-dev/tox/compare/4.28.0...4.28.1)

</details>

---

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---

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requirements-dev.txt

@@ -1,6 +1,6 @@
 -r requirements.txt
 -r requirements-test.txt
-tox==4.28.0
+tox==4.28.1
 wheel==0.46.1
 Sphinx==7.4.7
 sphinx-rtd-theme==3.0.2