Update docs/requirements.txt (#333)

Also required pinning to Python 3.11 in CI due to an odd pip error.

Author: brettcannon

.github/workflows/main.yml

@@ -28,7 +28,7 @@ jobs:
 
       - uses: actions/setup-python@v4
         with:
-          python-version: "3.x"
+          python-version: "3.11"
 
       - name: Install distro packages
         run: sudo apt-get install -qq pandoc