Bug: Duplicate articles for 3-letter code

[bittlingmayer]

A lot of languages at the bottom of https://machinetranslate.org/languages seem to be not supported by any API yet, e.g. https://machinetranslate.org/wln - 0 APIs.

It turns out that these are simply languages for which a 2-letter code exists, but for which an API like Baidu chose to use the 3-letter code, and we generated a page for both codes.

https://github.com/search?q=repo%3Amachinetranslate%2Fmachinetranslate.org%20wln&type=code

So really we only need to list wa.

https://machinetranslate.org/wa
So for language for which a mapping to a canonical code exists in api_languages.json, we should remove the listing of the non-canonical code from languages.json:

[bittlingmayer]

I assume this got added during 8fcd474