Text Google Translate doesn't work for ZH-Hant

[igs-kumayu]

Text Google Translate doesn't work for ZH-Hant-TW
Can you check it issue?

[OdlsCheng]

In google document, it say:

Chinese (Simplified)    zh-CN or zh  
Chinese (Traditional)   zh-TW  

However, zh-CN and zh-TW work correctly, but zh don't.
Modifying zh in supported_lang to zh-CN and zh-TW should resolve the issue.

Or display as zh (simple) and zh (Tradit) in the UI.
Then convert to zh-CN and zh-TW in the execute function only for API calls.