Bump furo from 2023.3.27 to 2023.5.20

Bumps [furo](https://github.com/pradyunsg/furo) from 2023.3.27 to 2023.5.20.
- [Release notes](https://github.com/pradyunsg/furo/releases)
- [Changelog](https://github.com/pradyunsg/furo/blob/main/docs/changelog.md)
- [Commits](pradyunsg/furo@2023.03.27...2023.05.20)

---
updated-dependencies:
- dependency-name: furo
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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