He isn't saying "that's _a_ great hustle, Ruby," he's saying "that's great hustle, Ruby." It's sports talk.
One of many meanings of the word "to hustle" is to move quickly, to rush, to show a burst of speed. In sports, it is also used as a noun, meaning "speed" or "energy." A coach might say to his players "Come on, folks, let's see some hustle," meaning he wants to see more speed and more energy." "That's good hustle" is complimenting someone on their speed. That's what Matt Damon is doing here.
In another context, the phrase "_a_ great hustle" would suggest a completely different meaning of the word hustle: a scam, a swindle, a racket, a way of cheating someone... often, by pretending to be a poor player at some game such as pool (pocket billiards) or poker, to lure someone into playing against you for money.