Merge pull request #148 from NOAA-GFDL/fix-docs

upgrade the version of sphinx-rtd-theme to fix "style is undefined"

.github/workflows/documentation.yml

@@ -13,7 +13,8 @@ jobs:
       - uses: actions/setup-python@v3
       - name: Install dependencies
         run: |
-          pip install 'sphinx<=7.3.7' sphinx_rtd_theme myst_parser renku-sphinx-theme
+          pip install sphinx renku-sphinx-theme sphinx-rtd-theme          
+          pip install --upgrade sphinx-rtd-theme
       - name: Sphinx build
         run: |
           sphinx-build docs build