Raise Python version to match Sphinx 7.2.6

.github/workflows/builds.yml

@@ -22,10 +22,10 @@ jobs:
       uses: actions/checkout@v3
       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 Requirements
       run: |
         if [[ ${{ matrix.format }} != "html" ]]; then