Bump sphinx from 6.2.1 to 7.2.6 in /docs

Bumps [sphinx](https://github.com/sphinx-doc/sphinx) from 6.2.1 to 7.2.6.
- [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...v7.2.6)

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

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

Author: dependabot[bot]

docs/requirements.txt

@@ -1,7 +1,7 @@
 # File: docs/requirements.txt
 
 # Defining the exact version will make sure things don't break
-sphinx==6.2.1
+sphinx==7.2.6
 sphinx_rtd_theme==1.2.0
 readthedocs-sphinx-search==0.3.1
 rstcheck==6.1.1