Use Python 3.11 for CD workflow (following #445)

Author: tomwhite

.github/workflows/cd.yml

@@ -19,7 +19,7 @@ jobs:
       - uses: actions/checkout@v4
       - uses: actions/setup-python@v5
         with:
-          python-version: '3.10'
+          python-version: '3.11'
       - name: Install dependencies
         run: |
           python -m pip install --upgrade pip