Distance grabbers able to grab objects with secondary grab set to none

### Environment

* Code source: Tilia package manager
* Code version: 2.6.1
* Platform version: Unity 2021.3
* 3rd party dependencies: NA

### Steps to reproduce

Add an interactable to the scene and set secondary grab to none. Add a distance grabber to both aliases. Grab the object and then hold it out and point at it with the other controller - the distance grabber indicator will appear and you can initiate a grab.

> Do not upload custom projects with custom code to demonstrate the issue.

### Expected behavior

Distance grabber will not activate on already grabbed objects - specifically with their secondary grab set to none.

### Current behavior

Distance grabber is able to grab an already grabbed object, even if secondary grab type is set to none.