Fix release

Author: c-w

.github/workflows/cd.yml

@@ -13,7 +13,10 @@ jobs:
       - uses: actions/checkout@v2
       - uses: actions/setup-python@v2
         with:
-          python-version: '3.7'
+          python-version: '3.9'
+
+      - name: 'Upgrade pip and setuptools'
+        run: python -m pip install --upgrade pip setuptools wheel
 
       - name: Build
         run: python setup.py sdist bdist_wheel