Add step to create 404.html in deploy workflow

Added step to create 404.html for History API routing.

Author: rdmueller

.github/workflows/deploy.yml

@@ -48,7 +48,10 @@ jobs:
       - name: Build website (prebuild runs render-docs.js)
         working-directory: ./website
         run: npm run build
-
+        
+      - name: Create 404.html for History API routing
+        run: cp website/dist/index.html website/dist/404.html
+          
       - name: Upload artifact
         uses: actions/upload-pages-artifact@v3
         with: