Part of epic #10524

This issue allows Singapore-based merchants to provide a Tax ID and required business details.

This includes frontend/UI changes (e.g. wording), and any backend changes required.

Singapore-specific details:

• Tax ID name: Unique Entity Number (UEN) or GST Registration Number (GST Reg No.)
• Tax name: GST
• See Taxamo settings for additional statements required when accepting Tax IDs
  • See the Taxamo test account creds on secret store: Taxamo Transact (Test).
• See the WooPayments VAT Matrix for Tax Id and Tax Name

Tax ID format

Source: IRAS

Unique Entity Number (UEN)

GST Registration Number (GST Reg No.)

Messaging requirements

Ensure that there is a message beside the GST number input box regarding self-declaration:

"By inputting your GST number you confirm you are a Singapore GST registered business and you are going to account for the GST".