Bank transfer: Auto-ignore all 0-valued transactions (fixes #5168) (#5620)

* Bank transfer: Auto-ignore all 0-valued transactions (fixes #5168)

* Fix failing test

src/pretix/plugins/banktransfer/tasks.py

@@ -419,6 +419,11 @@ def process_banktransfers(self, job: int, data: list) -> None:
                 )
 
                 for trans in transactions:
+                    if trans.amount == Decimal("0.00"):
+                        # Ignore all zero-valued transactions
+                        trans.state = BankTransaction.STATE_DISCARDED
+                        trans.save()
+                        continue
                     # Whitespace in references is unreliable since linebreaks and spaces can occur almost anywhere, e.g.
                     # DEMOCON-123\n45 should be matched to DEMOCON-12345. However, sometimes whitespace is important,
                     # e.g. when there are two references. "DEMOCON-12345 DEMOCON-45678" would otherwise be parsed as

src/tests/plugins/banktransfer/test_import.py

@@ -504,7 +504,7 @@ def test_valid_plus_invalid_match(env, orga_job):
         'payer': 'Karla Kundin',
         'reference': 'Bestellungen DUMMY-1Z3AS DUMMY-99999',
         'date': '2016-01-26',
-        'amount': '.00'
+        'amount': '2.00'
     }])
     with scopes_disabled():
         job = BankImportJob.objects.last()