Entity has()/get() for relation properties are missing autocomplete

[dereuromark]

//working
$releaseElement->has('release_group_id')

// not working
$releaseElement->has('release_group')
$releaseElement->get('release_group')

We should add all properties into it that are part of dependency relations and as such also exist usually.

[dereuromark]

Solved in c63caec