fix: Tax region + rates clean up (#9279)

What
- Require `code` on Tax Rates
- Update dashboard to account for non-nullable code on Tax Rates

- Include `automatic_taxes` in API Route response

Closes CC-524 CC-525

packages/modules/tax/integration-tests/utils/setup-tax-structure.ts

@@ -27,11 +27,11 @@ export const setupTaxStructure = async (service: ITaxModuleService) => {
   const [us, dk, de, ca] = await service.createTaxRegions([
     {
       country_code: "US",
-      default_tax_rate: { name: "US Default Rate", rate: 2 },
+      default_tax_rate: { name: "US Default Rate", rate: 2, code: "US" },
     },
     {
       country_code: "DK",
-      default_tax_rate: { name: "Denmark Default Rate", rate: 25 },
+      default_tax_rate: { name: "Denmark Default Rate", rate: 25, code: "DK" },
     },
     {
       country_code: "DE",
@@ -43,7 +43,7 @@ export const setupTaxStructure = async (service: ITaxModuleService) => {
     },
     {
       country_code: "CA",
-      default_tax_rate: { name: "Canada Default Rate", rate: 5 },
+      default_tax_rate: { name: "Canada Default Rate", rate: 5, code: "CA" },
     },
   ])