[Backport branch-8-6] upgrade to Sphinx 9.0 release (#1054)

* update to Sphinx 9.0

* ugrade to Sphinx 9.0.1 release

---------

Co-authored-by: Jeff McKenna <[email protected]>

Author: github-actions[bot]

requirements.txt

@@ -1,6 +1,6 @@
 alabaster==1.0.0
-docutils==0.21.2
-sphinx==8.2.3
+docutils==0.22.3
+sphinx==9.0.1
 sphinx-copybutton==0.5.2
 sphinxcontrib-jquery==4.1
 --extra-index-url https://test.pypi.org/simple/