Reddit logo on website. Jakub Porzycki | Nurphoto | Getty ImagesReddit is ramping up efforts to attract more users outside of the U.S., putting countries like India and Brazil in focus as it looks to unlock new advertising opportunities, a top company executive told CNBC.In a wide-ranging interview, Jen Wong, chief operating officer of Reddit, said other platforms have 80% to 90% of users outside of the U.S. while about half of her company's current users are based internationally."So that point...