Let's say we have the following type:

```typescript
type Chapter = {
  title: string
  next: Chapter | null
}
```

Here, `Chapter` type is recursive, referencing itself.
Typelizer can generate this kind of type, but currently it tries
to import itself and causes an error.
This commit fixes this issue by ignoring itself from import target.
Note that I added spec for Alba only since that was my case,
but please tell me if I should add more specs for other serializers.