chg: ✅ Added tests for null tax rates

Author: jonathanMindee

tests/documents/test_invoice.py

@@ -290,6 +290,7 @@ def test_empty_object_works():
     invoice = Invoice()
     assert invoice.total_tax.value is None
 
+
 def test_null_tax_rates_dont_raise():
     invoice = Invoice(
         locale="fr",

tests/documents/test_receipt.py

@@ -179,3 +179,5 @@ def test_compare_4(receipt_object_from_scratch):
 def test_empty_object_works():
     receipt = Receipt()
     assert receipt.total_tax.value is None
+
+