cleanup: Fix array iteration off by one
cleanup: Fix array iteration off by one

_removeInternalModels loop had a off by one error that was hidden by a
superfluous call to `isResolvedValue`.

`isResolvedValue` is pointless in this place, as in a tracked array
all of the models are always resolved

hjdivad/ember-m3,hjdivad/ember-m3,hjdivad/ember-m3