Bump sphinx from 5.2.3 to 5.3.0 in /docs (#3333)

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

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

docs/requirements.txt

@@ -1,7 +1,7 @@
 # Used by ReadTheDocs; pinned requirements for stability.
 
 myst-parser==0.18.1
-Sphinx==5.2.3
+Sphinx==5.3.0
 # Older versions break Sphinx even though they're declared to be supported.
 docutils==0.19
 sphinxcontrib-programoutput==0.17