Bump sphinx-toolbox from 4.0.0 to 4.1.2

Bumps [sphinx-toolbox](https://github.com/sphinx-toolbox/sphinx-toolbox) from 4.0.0 to 4.1.2.
- [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@v4.0.0...v4.1.2)

---
updated-dependencies:
- dependency-name: sphinx-toolbox
  dependency-version: 4.1.2
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

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Author: dependabot[bot]