Bump sphinx from 8.1.3 to 8.2.1 (#661)

Bumps [sphinx](https://github.com/sphinx-doc/sphinx) from 8.1.3 to 8.2.1.
- [Release notes](https://github.com/sphinx-doc/sphinx/releases)
- [Changelog](https://github.com/sphinx-doc/sphinx/blob/v8.2.1/CHANGES.rst)
- [Commits](sphinx-doc/sphinx@v8.1.3...v8.2.1)

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

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

pyproject.toml

@@ -34,7 +34,7 @@ docs = [
   "sphinx-copybutton==0.5.2",
   "sphinx-design==0.6.1",
   "sphinx-issues==5.0.0",
-  "sphinx==8.1.3",
+  "sphinx==8.2.1",
   "sphinxext-opengraph==0.9.1",
 ]
 tests = ["pytest<9", "pytest-lazy-fixtures"]