Fix docs build

Author: codingjoe

.github/workflows/ci.yml

@@ -6,6 +6,7 @@ jobs:
     steps:
       - uses: actions/setup-python@v2
       - uses: actions/checkout@v2
+      - run: python -m pip install --upgrade pip setuptools wheel
       - run: python -m pip install -r requirements.txt
       - run: python setup.py develop
       - run: python setup.py build_sphinx -W