⬆️ Bump quantecon/actions from 0.8.0 to 0.9.0 (#585)

Bumps [quantecon/actions](https://github.com/quantecon/actions) from 0.8.0 to 0.9.0.
- [Release notes](https://github.com/quantecon/actions/releases)
- [Changelog](https://github.com/QuantEcon/actions/blob/main/CHANGELOG.md)
- [Commits](QuantEcon/actions@v0.8.0...v0.9.0)

---
updated-dependencies:
- dependency-name: quantecon/actions
  dependency-version: 0.9.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

.github/workflows/publish.yml

@@ -104,7 +104,7 @@ jobs:
       # Deploy to GitHub Pages + publish release assets (html archive, checksum, manifest)
       - name: Deploy to GitHub Pages
         id: deployment
-        uses: quantecon/actions/publish-gh-pages@v0.8.0
+        uses: quantecon/actions/publish-gh-pages@v0.9.0
         with:
           build-dir: _build/html
           cname: python-programming.quantecon.org