Bump sphinx from 8.0.2 to 8.1.3

Bumps [sphinx](https://github.com/sphinx-doc/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/v8.1.3/CHANGES.rst)
- [Commits](sphinx-doc/sphinx@v8.0.2...v8.1.3)

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

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

pyproject.toml

@@ -51,7 +51,7 @@ plotly-static = ["kaleido"]
 decimation = ["open3d"]
 smooth = ["PyMCubes"]
 docs = [
-    "sphinx==8.0.2",
+    "sphinx==8.1.3",
     "sphinx-click==6.0.0",
     "furo==2024.8.6",
     "sphinx-autodoc-typehints==2.4.4",