Bump sphinx from 6.2.1 to 8.2.3 in /docs (#2516)

Bumps [sphinx](https://github.com/sphinx-doc/sphinx) from 6.2.1 to 8.2.3.
- [Release notes](https://github.com/sphinx-doc/sphinx/releases)
- [Changelog](https://github.com/sphinx-doc/sphinx/blob/master/CHANGES.rst)
- [Commits](sphinx-doc/sphinx@v6.2.1...v8.2.3)

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

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

docs/build_requirements.txt

@@ -1,4 +1,4 @@
-Sphinx==6.2.1
+Sphinx==8.2.3
 furo==2024.4.27
 myst-parser==3.0.1
 sphinx-copybutton==0.5.0