Update enums3.rs

This will cause the function to keep failing, In order to pass I needed to remove a pair of quotes, not sure if this was intentional and my solution was wrong, but this was the only solution I was able to come up with.

exercises/enums/enums3.rs

@@ -51,7 +51,7 @@ mod tests {
             position: Point { x: 0, y: 0 },
             color: (0, 0, 0),
         };
-        state.process(Message::ChangeColor((255, 0, 255)));
+        state.process(Message::ChangeColor(255, 0, 255));
         state.process(Message::Echo(String::from("hello world")));
         state.process(Message::Move(Point { x: 10, y: 15 }));
         state.process(Message::Quit);