build(deps): bump sphinx from 7.2.6 to 8.1.3

Bumps [sphinx](https://github.com/sphinx-doc/sphinx) from 7.2.6 to 8.1.3.
- [Release notes](https://github.com/sphinx-doc/sphinx/releases)
- [Changelog](https://github.com/sphinx-doc/sphinx/blob/master/CHANGES.rst)
- [Commits](sphinx-doc/sphinx@v7.2.6...v8.1.3)

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

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

pyproject.toml

@@ -82,7 +82,7 @@ doc = [
     "numpydoc==1.8.0",
     "pillow==10.4.0",
     "docker>=7.1.0",
-    "Sphinx==7.2.6",
+    "Sphinx==8.1.3",
     "sphinx-copybutton==0.5.2",
     "sphinx-gallery==0.18.0",
 ]
@@ -101,7 +101,7 @@ dev = [
     "docker>=7.1.0",
     "pytest==8.3.3",
     "pytest-cov==4.1.0",
-    "Sphinx==7.2.6",
+    "Sphinx==8.1.3",
     "sphinx-copybutton==0.5.2",
     "sphinx-gallery==0.18.0",
     "pre-commit==3.3.3",