Allow creating a model that does not 'allow' anyone.

**Is your feature request related to a problem? Please describe.**

I am creating a model that my users do not access directly. As such, I do not want to be forced to _allow_ anyone.

**Describe the solution you'd like**

Either:
- simply deny by default if `.authorization()` is not called
- provide `allow.nobody()` as in `.authorization((allow) => [allow.nobody()])` which allows the user to be explicitly deny access.

**Describe alternatives you've considered**

As a temporary workaround, I've chosen to use `@auth(rules: [{allow: owner, ownerField: "_never_"}])` which is a field that wont be populated. I still see, however, that there is an unwanted field resolver defined automatically called `MyModel_never_DataResolverFn`.

```typescript

.authorization((allow) => [allow.ownerDefinedIn('_never_')]);

```

**Additional context**

Add any other context or screenshots about the feature request here.