Just ignore the cat poo eating .....the bigger deal you make of it the more she'll do it !
Or when you think she's heading for it (well before she gets there) distract her and play a game with her instead .
Ignore the bad ....reward the good . Dont reward her by shouting or stroking or whatever you do to distract her when she's eating it ......bribing her with treats at the scene of the crime is rewarding the bad ......does that make sense ?