add partial contract tests

backend/tests/factories/contracts.py

@@ -3,6 +3,7 @@ from .forms import form_factory
 
 def contract_factory(**kwargs):
     data = dict(
+        id=1,
         firstname="test",
         lastname="test",
         email="test@test.test",
@@ -67,6 +68,9 @@ def contract_body_factory(**kwargs):
         phone="00000000",
         payment_method="cheque",
         cheque_quantity=1,
+        products=[],
+        cheques=[],
+        form_id=1
     )
     data.update(kwargs)
     return data