fixes#3011
In https://github.com/nim-lang/Nim/pull/23532, meta fields that defined
in the object are handled.
In this PR, RefObjectTy is handled as well:
```nim
type
Type = ref object
context: ref object
```
Ref alias won't trigger mata fields checking so there won't have
cascaded errors on `TypeBase`.
```nim
type
TypeBase = object
context: ref object
Type = ref TypeBase
context: ref object
```