By Braden Chalker FROM MERCEDES-BENZ STADIUM – Atlanta United’s Leagues Cup campaign came to a screeching halt after a 0-0 (5-3 on penalties) defeat to Liga MX side Santos Laguna Sunday night. It was a win-or-go-home scenario for both Atlanta and Santos as DC United already claimed first place in East Group 7 with six points. Atlanta entered the match with one point in second place while Santos were in third with zero points, meaning the winner of the match would advance to the Leagues Cup Round of 32 alongside DC. Neither side were able to find the breakthrough in the first half even though b…