update Python version from 3.12 to 3.13 in GitHub Actions workflow

Author: rongxin-liu

.github/workflows/main.yml

@@ -28,7 +28,7 @@ jobs:
       - name: Setup Python
         uses: actions/setup-python@v5
         with:
-          python-version: '3.12'
+          python-version: '3.13'
 
       - name: Only use `build` and `features`, if any, from devcontainer.json
         run: |