Bump furo and black (#2385)

Updates `furo` from 2024.7.18 to 2024.8.6
- [Release notes](https://github.com/pradyunsg/furo/releases)
- [Changelog](https://github.com/pradyunsg/furo/blob/main/docs/changelog.md)
- [Commits](pradyunsg/furo@2024.07.18...2024.08.06)

Updates `black` from 24.4.2 to 24.8.0
- [Release notes](https://github.com/psf/black/releases)
- [Changelog](https://github.com/psf/black/blob/main/CHANGES.md)
- [Commits](psf/black@24.4.2...24.8.0)

---
updated-dependencies:

  dependency-group: python-packages
- dependency-name: furo
  dependency-type: direct:development
  update-type: version-update:semver-minor
  dependency-group: python-packages
- dependency-name: black
  dependency-type: direct:development
  update-type: version-update:semver-minor
  dependency-group: python-packages
...

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

* Pin Sphinx==7.4.7

---------

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

setup.py

@@ -71,7 +71,7 @@ def get_version():
     extras_require={
         "docs": [
             "Sphinx==7.4.7",
-            "furo==2024.7.18",
+            "furo==2024.8.6",
             "sphinx-autobuild",
             "codespell>=2.2.5",
             "blacken-docs",
@@ -84,7 +84,7 @@ def get_version():
             "pytest-xdist>=2.2.1",
             "pytest-asyncio>=0.17",
             "beautifulsoup4>=4.8.1",
-            "black==24.4.2",
+            "black==24.8.0",
             "blacken-docs==1.18.0",
             "pytest-timeout>=1.4.2",
             "trustme>=0.7",