[Shipping Labels] Woomob 891 make hs tariff number mandatory for eu destination

[RafaelKayumov]

Part of: WOOMOB-891

Description

Makes the HS tariff number required for shipments where destination country is in EU.

• Adds explicit isHSTariffNumberRequired var for WooShippingCustomsItemViewModel that's driven by destination country being a member of Country.countriesFollowingEUCustoms.
• isHSTariffNumberRequired participates in requiredInformationIsEntered calculation.
• Makes the HS tariff number field as a required field in the WooShippingCustomsItem view:
  • Renders "value required" warning if destination country is EU and the HS tariff number is empty
  • Renders red border if destination country is EU and the HS tariff number is empty
  • Removes "Optional" placeholder in case if the HS tariff number is required.

Testing Steps

• Navigate to a completed order with an unfulfilled shipment
• Just in case make sure the total value for products in the shipment is below the 2500 threshold
• Set a foreign destination address - for example some public address in Canada
• Fill in missing shipment details.
• Make sure the HS tariff field for customs form product items is optional
• Switch shipment destination address to a EU country. Consider using some public address.
• Make sure the customs section becomes incomplete.
• Make sure the product HS tariff field is now a required field.
• Enter HS tariff numbers for incomplete product customs cards and save the form
• Make sure the customs section is now complete
• Make sure label purchase flow is unlocked

---

• I have considered if this change warrants user-facing release notes and have added them to RELEASE-NOTES.txt if necessary.

[wpmobilebot]

📲 You can test the changes from this Pull Request in WooCommerce iOS Prototype by scanning the QR code below to install the corresponding build.

	App Name	WooCommerce iOS Prototype
	Build Number	pr15946-c249322
	Version	22.9
	Bundle ID	com.automattic.alpha.woocommerce
	Commit	c249322
	Installation URL	2bcu5t4pu1n58

Automatticians: You can use our internal self-serve MC tool to give yourself access to those builds if needed.

[wpmobilebot]

Version 22.9 has now entered code-freeze, so the milestone of this PR has been updated to 23.0.

[itsmeichigo]

This works as described 👍 I left some non-blocking comments.

[itsmeichigo]

Nit: redundant line.

[itsmeichigo]

Nit: I didn't know that && takes priority over ||. Still, should we add braces or split this into two properties for readability?

[RafaelKayumov]

👌 Gonna add braces for readability