remove board from constructor

app/src/main/java/chess/model/Game.java

@@ -20,8 +20,8 @@ public class Game {
 		Draw, Check, CheckMate, OnGoing, Pat;
 	}
 
-	public Game(ChessBoard board) {
-		this.board = board;
+	public Game() {
+		this.board = new ChessBoard();
 		this.movesHistory = new Stack<>();
 		this.traitsPos = new HashMap<>();
 	}