de-duplicate contract issues

contracts/management/commands/import_old_contracts.py

@@ -75,9 +75,17 @@ class Command(BaseCommand):
         )
 
     def use_issue(self, name: str) -> None:
-        issue = ContractIssue.objects.filter(name=name).first()
+        issues = ContractIssue.objects.filter(name=name).all()
 
-        if issue is None:
+        if len(issues) != 0:
+            issue = issues[0]
+        elif len(issues) > 1:
+            for issue in issues[1:]:
+                for contract in issue.contracts:
+                    contract.issues.add(issue)
+
+                issue.delete()
+        else:
             issue = ContractIssue(name=name)
             issue.save()
 
@@ -1375,6 +1383,7 @@ class Command(BaseCommand):
                 Contract,
                 ContractType,
                 ContractFilingArea,
+                ContractIssue,
                 ContractFile,
                 Contractee,
                 ContracteeSignature,