TypeError: imports is not iterable after upgrading to Storybook 8.6.9 with Angular 18

[Behrouz-B]

After upgrading our project to Storybook version 8.6.9, we've encountered issues where some of our tests are failing. The error message we receive during the mounting of story components is: TypeError: imports is not iterable.

Steps to Reproduce:

1. Update the Angular 18 project to Storybook 8.6.9.
2. Run tests or try to mount story components using createMountable(Primary({}));.
3. Observe the error: TypeError: imports is not iterable.

Expected Behavior:
The story components should mount without errors, allowing tests to pass successfully.

Actual Behavior:
The error TypeError: imports is not iterable is thrown, causing tests to fail upon mounting certain story components.

[zargham-k]

@Marklb @shilman would you be able to look into it? this is blocking us to upgrade to Angular v19.

[shilman]

@valentinpalkovic for your radar