Bump sphinx-rtd-theme from 1.3.0 to 2.0.0 (#1036)

Bumps [sphinx-rtd-theme](https://github.com/readthedocs/sphinx_rtd_theme) from 1.3.0 to 2.0.0.
- [Changelog](https://github.com/readthedocs/sphinx_rtd_theme/blob/master/docs/changelog.rst)
- [Commits](readthedocs/sphinx_rtd_theme@1.3.0...2.0.0)

---
updated-dependencies:
- dependency-name: sphinx-rtd-theme
  dependency-type: direct:development
  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>

setup.py

@@ -83,7 +83,7 @@
             # Docs.
             "Sphinx==7.2.5 ; python_version>='3.9'",
             "sphinx-autobuild==2021.3.14 ; python_version>='3.9'",
-            "sphinx-rtd-theme==1.3.0 ; python_version>='3.9'",
+            "sphinx-rtd-theme==2.0.0 ; python_version>='3.9'",
         ]
     },
     python_requires=">=3.5",