External objects added through customization have incorrect behaviour with EditConditionHides

Copy-paste the TestCode.h and TestCode.cpp into a module
Activate the customization in the StartupModule() function
```
FPropertyEditorModule& PropertyModule = FModuleManager::LoadModuleChecked<FPropertyEditorModule>("PropertyEditor");
PropertyModule.RegisterCustomPropertyTypeLayout(FDetailsLayoutTestConfig::StaticStruct()->GetFName(), FOnGetPropertyTypeCustomizationInstance::CreateStatic(&FDetailsLayoutTestConfigCustomization::MakeInstance));
```

Add the component to an actor
EXPECT: Component Settings -> Component String is not a visible property
Click "Show Component String"
EXPECT: Component String to become visible
Click Config->Object->External Settings-> Show External String
EXPECT: Conditionally Shown External String should become visible
ACTUAL: Is isn't visible. Deselecting the component and reselecting makes it visible