Use Language.LanguageCode as localization key, falling back to language.Lang

[razonyang]

Hugo supports localize time and dates since v0.87.0, but I'm stuck by specifying the language key that not defined in https://github.com/gohugoio/locales.

For example:

[zh_hans] # localization works as expected.
  languageName = "zh_hans"

[zh-cn]
  languageName = "zh-cn"
  locale = "zh_hans" # additional parameter to match the locale

• https://discourse.gohugo.io/t/is-it-possible-to-make-language-key-to-be-differenced-with-locale-name/35386

[github-actions]

This issue has been automatically marked as stale because it has not had recent activity. The resources of the Hugo team are limited, and so we are asking for your help.
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[github-actions]

This issue has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs.