Utilize action=query&format=json&meta=siteinfo to get the correct language code

For example for zh-yue:

https://zh-yue.wikipedia.org/w/api.php?action=query&format=json&meta=siteinfo

Returns yue for query.general.lang in the response

https://zh-classical.wikipedia.org/w/api.php?action=query&format=json&meta=siteinfo

Returns lzh

This would replace the mapping dictionary in WikidataDescriptionEditingController

See T212633 for the bug reported on Android

Testing criteria:

Wikidata description editing should work as expected for all languages, with specific attention paid to`zh-yue`, zh-classical, zh-min-nan, gsw, and any other language whose wikidata description language code doesn't match the domain

Also test places geography lookup (when you search for an article in any language and tap on the article, it should move the map to the correct location). Consolidated some Wikidata code along with this change that could affect that lookup.