chore(deps): update dependency tox to v4.28.4 (#833)

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)) | `==4.28.3` ->
`==4.28.4` |
[![age](https://developer.mend.io/api/mc/badges/age/pypi/tox/4.28.4?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![confidence](https://developer.mend.io/api/mc/badges/confidence/pypi/tox/4.28.3/4.28.4?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|

---

### Release Notes

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

###
[`v4.28.4`](https://redirect.github.com/tox-dev/tox/releases/tag/4.28.4)

[Compare
Source](https://redirect.github.com/tox-dev/tox/compare/4.28.3...4.28.4)

<!-- Release notes generated using configuration in .github/release.yml
at 4.28.4 -->

#### 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/3570](https://redirect.github.com/tox-dev/tox/pull/3570)0
- Pass ssh-agent variables by default by
[@&#8203;daniilgankov](https://redirect.github.com/daniilgankov) in
[https://github.com/tox-dev/tox/pull/3572](https://redirect.github.com/tox-dev/tox/pull/3572)

#### New Contributors

- [@&#8203;daniilgankov](https://redirect.github.com/daniilgankov) made
their first contribution in
[https://github.com/tox-dev/tox/pull/3572](https://redirect.github.com/tox-dev/tox/pull/3572)

**Full Changelog**:
tox-dev/tox@4.28.3...4.28.4

</details>

---

### Configuration

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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

---

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View the [repository job
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requirements-dev.txt

@@ -1,6 +1,6 @@
 -r requirements.txt
 -r requirements-test.txt
-tox==4.28.3
+tox==4.28.4
 wheel==0.46.1
 Sphinx==7.4.7
 sphinx-rtd-theme==3.0.2