ci(docs): push the generated tree to gh-pages

.github/workflows/ci.yaml

@@ -130,3 +130,10 @@ jobs:
               -T 'Argus Python Documentation versions' \
               -s -D \
               -o index.html
+          git config user.name github-actions
+          git config user.email github-actions@github.com
+          git add .
+          if [[ ! $(git diff --quiet) ]]; then
+            git commit -m "update index.html"
+            git push
+          fi