add child pages

Author: QiLi111

.github/workflows/pages.yml

@@ -47,7 +47,7 @@ jobs:
           JEKYLL_ENV: production
       - name: Upload artifact
         # Automatically uploads an artifact from the './_site' directory by default
-        uses: actions/upload-pages-artifact@v1
+        uses: actions/upload-pages-artifact@v3
 
   # Deployment job
   deploy: