Update Python version in github action

Python 3.7 is no longer supported by new releases of Sphinx

.github/workflows/html.yml

@@ -12,10 +12,10 @@ jobs:
       name: Checking out the code 🛒
       with:
         fetch-depth: 1
-    - name: Set up Python 3.7 🐍
+    - name: Set up Python 3.10 🐍
       uses: actions/setup-python@v4
       with:
-        python-version: 3.7
+        python-version: '3.10'
     - name: Install dependencies 👨‍👩‍👦
       run: |
           python -m pip install --upgrade pip