build(deps): 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]>

Author: dependabot[bot]

pyproject.toml

@@ -55,7 +55,7 @@ tests = [
     "regex==2024.9.11",
 ]
 doc = [
-    "Sphinx==8.0.2",
+    "Sphinx==8.1.3",
     "ansys-sphinx-theme[autoapi]==1.1.5",
     "build>= 0.10.0",
     "flit>=3.8.0",