Taxonomy not supporting LocaleProviderService node naming convention

This issue came up while testing the HIPPLUG-1480. As per current implementation, the name of the node under LocaleProviderService should follow the below pattern:
xx
xx-XX
xx_XX

Kindly read the comments at the bottom from Bert Leunis in HIPPLUG-1480:

In offline discussions I found out that the value of the hippotranslation:locale property on folders and documents is intentionally the name of the locale provider child node at /hippo:configuration/hippo:frontend/cms/cms-services/localeProviderService. So the node name can be "anything" and have language and country properties containing "en" and "gb" for example. The string "anything" is used as value in the hippotranslation:locale property on documents.

So if the taxonomy plugin creates a Locale for a document, it should use the "anything" value to look up the language and country properties from the localeProviderService child node. That would be an improvement to be built in too.

But unfortunately our documentation states: "Note that the "country" property in the locale provider service configuration does not have to be a real country code."[1] It does not even state that it should at least be well-formed according to the IETF standard. Which in the end will mean that some customers will be confronted with a backward compatible change, if they used a country code that does not "well-form".

[1] https://www.onehippo.org/library/concepts/translations/add-a-translatable-language.html