How can I create an Azure APIM subscription that is not related to any APIM Product?

As of today the product_id is defined as a required field in the azurerm_api_management_subscription resource.

At the same time APIM allows creating subscriptions that can:

  • Call any API
  • Call only one specific API
  • Any API that are included into a Product.

It looks like only the last option is supported by the azurerm.
How can utilize the other two options?