chore(deps): update dependency tox to v4.28.0 (#828)

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)) | `==4.27.0` ->
`==4.28.0` |
[![age](https://developer.mend.io/api/mc/badges/age/pypi/tox/4.28.0?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![confidence](https://developer.mend.io/api/mc/badges/confidence/pypi/tox/4.27.0/4.28.0?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|

---

### Release Notes

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

###
[`v4.28.0`](https://redirect.github.com/tox-dev/tox/releases/tag/4.28.0)

[Compare
Source](https://redirect.github.com/tox-dev/tox/compare/4.27.0...4.28.0)

<!-- Release notes generated using configuration in .github/release.yml
at 4.28.0 -->

#### What's Changed

- \[pre-commit.ci] pre-commit autoupdate by
[@&#8203;pre-commit-ci](https://redirect.github.com/pre-commit-ci)\[bot]
in[https://github.com/tox-dev/tox/pull/3548](https://redirect.github.com/tox-dev/tox/pull/3548)8
- \[docs] Document how to require a plugin by
[@&#8203;stephenfin](https://redirect.github.com/stephenfin) in
[https://github.com/tox-dev/tox/pull/3552](https://redirect.github.com/tox-dev/tox/pull/3552)
- \[pre-commit.ci] pre-commit autoupdate by
[@&#8203;pre-commit-ci](https://redirect.github.com/pre-commit-ci)\[bot]
in[https://github.com/tox-dev/tox/pull/3554](https://redirect.github.com/tox-dev/tox/pull/3554)4
- \[pre-commit.ci] pre-commit autoupdate by
[@&#8203;pre-commit-ci](https://redirect.github.com/pre-commit-ci)\[bot]
in[https://github.com/tox-dev/tox/pull/3558](https://redirect.github.com/tox-dev/tox/pull/3558)8
- Add `[testenv] constraints` option by
[@&#8203;stephenfin](https://redirect.github.com/stephenfin) in
[https://github.com/tox-dev/tox/pull/3556](https://redirect.github.com/tox-dev/tox/pull/3556)
- \[pre-commit.ci] pre-commit autoupdate by
[@&#8203;pre-commit-ci](https://redirect.github.com/pre-commit-ci)\[bot]
in[https://github.com/tox-dev/tox/pull/3562](https://redirect.github.com/tox-dev/tox/pull/3562)2
- Allow disabling plugins on a one-off by
[@&#8203;gaborbernat](https://redirect.github.com/gaborbernat) in
[https://github.com/tox-dev/tox/pull/3560](https://redirect.github.com/tox-dev/tox/pull/3560)

**Full Changelog**:
tox-dev/tox@4.27.0...4.28.0

</details>

---

### Configuration

📅 **Schedule**: Branch creation - At any time (no schedule defined),
Automerge - At any time (no schedule defined).

🚦 **Automerge**: Enabled.

♻ **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

---

This PR was generated by [Mend Renovate](https://mend.io/renovate/).
View the [repository job
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requirements-dev.txt

@@ -1,6 +1,6 @@
 -r requirements.txt
 -r requirements-test.txt
-tox==4.27.0
+tox==4.28.0
 wheel==0.46.1
 Sphinx==7.4.7
 sphinx-rtd-theme==3.0.2