Merge pull request #287 from helsing-ai/mz/hotfix-github-ci

Hotfix: Upgrade actions versions of book.yml to avoid CI failures

Author: mara-schulke

.github/workflows/book.yml

@@ -30,7 +30,7 @@ jobs:
         uses: peaceiris/[email protected]
       - run: cd docs && mdbook build
       - name: Upload artifacts
-        uses: actions/upload-pages-artifact@v2
+        uses: actions/upload-pages-artifact@v3
         with:
           path: 'docs/book'
       - name: Deploy to GitHub Pages