Loose belt not sorting "MIXED"

Issue description

The loose sorters will nto sort the "Mixed" cargo on the belts.

Reproduction steps

1. Get mixed lose of dirt and rock
2. Hook up loose belts to some loose sorters
3. set some to dirt and some to rock to sort out the loose products
4. watch it not sort anything...

Game version and build number

v0.8.8A (b628)

Which branch of the game are you on?

Experimental

Operating system

Windows

Also if you Unity remove the "Mixed" loose it gets Voided vs sent to the shipyard

https://coigame.com/Topic/21216/Mixed-Mined-Material-does-not-get-sent-to-Shipyard