'checkLocalCircular' is to strict

[sebilasse]

latest module and node version:

checkLocalCircular is to strict :

Let's say in a file I have

"definitions": {
  "array": {
    "type": "array",
    "items": {"$ref": "#"}
  }
}

but this definition is NOT used anywhere inside the file.

Still I get
[Error: Circular self reference]

[sebilasse]

I would expect it to leave the $ref intact when the file has an unused definition like above rather than throwing an error.
Only if elem.from in the definition has any counterparts (in the same file) referencing it in elem.to it should throw the error.