Manually specify python version in docs ci

.github/workflows/documentation.yml

@@ -6,6 +6,8 @@ jobs:
     steps:
       - uses: actions/checkout@v3
       - uses: actions/setup-python@v4
+        with:
+          python-version: "3.12"
       - name: Install dependencies
         run: |
           python -m pip install --upgrade pip