Bump the production group with 2 updates

Bumps the production group with 2 updates: [sphinx](https://github.com/sphinx-doc/sphinx) and [sphinx-rtd-theme](https://github.com/readthedocs/sphinx_rtd_theme).


Updates `sphinx` from 8.0.2 to 8.1.3
- [Release notes](https://github.com/sphinx-doc/sphinx/releases)
- [Changelog](https://github.com/sphinx-doc/sphinx/blob/master/CHANGES.rst)
- [Commits](sphinx-doc/sphinx@v8.0.2...v8.1.3)

Updates `sphinx-rtd-theme` from 3.0.0 to 3.0.1
- [Changelog](https://github.com/readthedocs/sphinx_rtd_theme/blob/master/docs/changelog.rst)
- [Commits](readthedocs/sphinx_rtd_theme@3.0.0...3.0.1)

---
updated-dependencies:
- dependency-name: sphinx
  dependency-type: direct:production
  update-type: version-update:semver-minor
  dependency-group: production
- dependency-name: sphinx-rtd-theme
  dependency-type: direct:production
  update-type: version-update:semver-patch
  dependency-group: production
...

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