ci: looks like we can't use env-vars in here

Author: ctron

.github/workflows/pages.yaml

@@ -40,7 +40,7 @@ jobs:
         uses: actions/download-artifact@v4
         with:
           name: book
-          path: $GITHUB_WORKSPACE/site/public/guide
+          path: site/public/guide
 
       - name: Dump | Site
         run: |