build: workaround for vue router in gh pages

Author: liborjelinek

.github/workflows/publish.yml

@@ -35,6 +35,8 @@ jobs:
         run: npm ci
       - name: Build
         run: npm run generate
+      - name: Workaround for Vue Router
+        run: cp ./.output/public/index.html ./.output/public/404.html
       - name: Upload artifact
         uses: actions/upload-pages-artifact@v3
         with: