WASHINGTON — Ukrainian President Volodymyr Zelensky on Sunday said he is still hoping to land a major deal to buy advanced US military drones, saying it would be a potentially “huge’’ game-changer in the war. His comments came as he warned that Ukraine was set to be brutally pummeled by Russia by air again for the second week in a row. Zelensky argued that fusing the dramatic advancements Ukraine has made with its drone technology because of its battlefield experience against Moscow with