Update publish-doc.yml

After adding linkchecker the output of generated site is now generated under a `html` sub directory.

Author: demeringo

.github/workflows/publish-doc.yml

@@ -46,7 +46,7 @@ jobs:
           # Delete the ref to avoid keeping history.
           git update-ref -d refs/heads/gh-pages
           rm -rf *
-          mv ../book/* .
+          mv ../book/html/* .
           git add .
           git commit -m "Deploy $GITHUB_SHA to gh-pages"
-          git push --force --set-upstream origin gh-pages
+          git push --force --set-upstream origin gh-pages