Buildiing an English file and a translated version at the same time is order specific

To build a translated version of axe-core, you run the build command by passing the `--lang` option. E.g. `npm run build -- --lang=es`. You can even pass multiple langs `npm run build -- --lang=es,ja` to build multiple files at a time. However, you cannot pass `en` as a lang option as the last part and have it work. `npm run build -- --lang=es,en` will output `axe.js` with Spanish translations, while `npm run build -- --lang=en,es` appears to work correctly.