Bump furo from 2023.3.27 to 2023.5.20 (#325)

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](https://github.com/pradyunsg/furo/compare/2023.03.27...2023.05.20)

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

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

poetry.lock

@@ -264,20 +264,20 @@ test = ["pytest (>=6)"]
 
 [[package]]
 name = "furo"
-version = "2023.3.27"
+version = "2023.5.20"
 description = "A clean customisable Sphinx documentation theme."
 category = "main"
 optional = true
 python-versions = ">=3.7"
 files = [
-    {file = "furo-2023.3.27-py3-none-any.whl", hash = "sha256:4ab2be254a2d5e52792d0ca793a12c35582dd09897228a6dd47885dabd5c9521"},
-    {file = "furo-2023.3.27.tar.gz", hash = "sha256:b99e7867a5cc833b2b34d7230631dd6558c7a29f93071fdbb5709634bb33c5a5"},
+    {file = "furo-2023.5.20-py3-none-any.whl", hash = "sha256:594a8436ddfe0c071f3a9e9a209c314a219d8341f3f1af33fdf7c69544fab9e6"},
+    {file = "furo-2023.5.20.tar.gz", hash = "sha256:40e09fa17c6f4b22419d122e933089226dcdb59747b5b6c79363089827dea16f"},
 ]
 
 [package.dependencies]
 beautifulsoup4 = "*"
 pygments = ">=2.7"
-sphinx = ">=5.0,<7.0"
+sphinx = ">=6.0,<8.0"
 sphinx-basic-ng = "*"
 
 [[package]]