Fonts are not bundled if built on Windows

If the UI is built on a Windows machine (e.g., Windows 10) with:

npm install
npx gulp bundle

Then the produced bundle under build/ui-bundle.zip does not contain the font folder with the Roboto fonts. The URLs in css/site.css still refer to the unresolved ~@fontsource/roboto/files/roboto-*.woff2 font paths.