build(deps-dev): bump sphinx from 7.4.7 to 8.1.3 in /clients/python (#2063)

Bumps [sphinx](https://github.com/sphinx-doc/sphinx) from 7.4.7 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@v7.4.7...v8.1.3)

---
updated-dependencies:
- dependency-name: sphinx
  dependency-version: 8.1.3
  dependency-type: direct:development
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]

clients/python/poetry.lock

@@ -37,7 +37,7 @@ olot = ["olot"]
 optional = true
 
 [tool.poetry.group.docs.dependencies]
-sphinx = "^7.2.6"
+sphinx = ">=7.2.6,<9.0.0"
 furo = ">=2023.9.10,<2026.0.0"
 myst-parser = { extras = ["linkify"], version = ">=2,<5" }
 sphinx-autobuild = ">=2021.3.14,<2025.0.0"