Update xero_accounting.yaml

Correction on ENUMS for TaxNumberType

Author: wobinb

xero_accounting.yaml

@@ -21169,10 +21169,10 @@ components:
           description: Identifier of the regional type of tax number, such as US, UK, or other regional tax identifiers
           type: string
           enum:
-            - SSN
-            - EIN
-            - ITIN
-            - ATIN
+            - TAXNUMBERTYPE/SSN
+            - TAXNUMBERTYPE/EIN
+            - TAXNUMBERTYPE/ITIN
+            - TAXNUMBERTYPE/ATIN
         AccountsReceivableTaxType:
           description: The tax type from TaxRates
           type: string