Support locales Chromium disables

I notice that `workerd` appears to be using Chromium's locale data. This is unfortunate, since Chromium [deliberately](https://bugs.chromium.org/p/chromium/issues/detail?id=956072#c5) hobbles locale support to be in line with full translations of its own UI. This removes support for a substantial number of languages. Node.js and Edge appear to fix this, presumably by using alternative ICU data files.

This prevents me from using either Cloudflare Workers or `workerd` for any task that requires sorting strings in my native language, and since the client is just as likely to be Chrome I can't rely on the browser knowing how to do it either. While that can be worked around, the workarounds almost always involve running a server somewhere that _does_ know how to do collation.

Would it be possible to at least investigate including more complete locale data?