Bump sphinx-rtd-theme from 1.2.0 to 1.2.1

Bumps [sphinx-rtd-theme](https://github.com/readthedocs/sphinx_rtd_theme) from 1.2.0 to 1.2.1.
- [Changelog](https://github.com/readthedocs/sphinx_rtd_theme/blob/master/docs/changelog.rst)
- [Commits](readthedocs/sphinx_rtd_theme@1.2.0...1.2.1)

---
updated-dependencies:
- dependency-name: sphinx-rtd-theme
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

setup.py

@@ -65,6 +65,6 @@
             "aioresponses==0.7.4",
             "black==23.3.0",
         ],
-        "docs": ["sphinx >= 1.4", "sphinx_rtd_theme==1.2.0"],
+        "docs": ["sphinx >= 1.4", "sphinx_rtd_theme==1.2.1"],
     },
 )