Caused by a change in FactoryBot 5. Associations in factories are now constructed using the same strategy as the base object, meaning that using `build` to construct an object will also construct the associations using `build`. This meant that overriding `create` to do `build` + `save` broke the way that associations were constructed. https://github.com/thoughtbot/factory_bot/blob/master/GETTING_STARTED.md#associations