fix ! ChoiceFieldWithEmptyDisplay not found in registry during sync flex fields (#266)

Author: vitali-yanushchyk-valor

src/country_workspace/contrib/hope/apps.py

@@ -4,6 +4,7 @@
 from .lookups import FinancialInstitutionChoice
 from .phone_numbers import PhoneNumberField
 from .beneficiary_reference import BeneficiaryReferenceModelChoiceField
+from .required_choice_field import ChoiceFieldWithEmptyDisplay
 
 
 class Config(AppConfig):
@@ -25,6 +26,7 @@ def ready(self) -> None:
         field_registry.register(FinancialInstitutionChoice)
         field_registry.register(PhoneNumberField)
         field_registry.register(BeneficiaryReferenceModelChoiceField)
+        field_registry.register(ChoiceFieldWithEmptyDisplay)
 
         from country_workspace.contrib.hope.validators import FullHouseholdValidator
         from country_workspace.validators.registry import beneficiary_validator_registry