Bump sphinx-toolbox from 3.8.0 to 3.8.1

Bumps [sphinx-toolbox](https://github.com/sphinx-toolbox/sphinx-toolbox) from 3.8.0 to 3.8.1.
- [Release notes](https://github.com/sphinx-toolbox/sphinx-toolbox/releases)
- [Changelog](https://github.com/sphinx-toolbox/sphinx-toolbox/blob/master/doc-source/changelog.rst)
- [Commits](sphinx-toolbox/sphinx-toolbox@v3.8.0...v3.8.1)

---
updated-dependencies:
- dependency-name: sphinx-toolbox
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <[email protected]>

requirements.txt

@@ -1,4 +1,4 @@
 sphinx==7.1.2
 sphinx-autobuild==2021.3.14
 sphinx-tabs==3.4.5
-sphinx-toolbox==3.8.0
+sphinx-toolbox==3.8.1