Previously, we had only set __webpack_public_path__ to a path which
caused webpack chunks to be loaded from the current origin which is
incorrect when STATIC_URL_PREFIX points to another origin.
This should fix the issue curretnly seen on gitea.com.
Co-authored-by: zeripath <art27@cantab.net>
Co-authored-by: Lauris BH <lauris@nix.lv>