Keira Knightley’s unforgettable green ‘Atonement’ dress is going up for sale

By Amarachi Orie, CNN (CNN) — Almost two decades after Keira Knightley bewitched audiences in the 2007 film, “Atonement,” the emerald-green silk dress she wore in a pivotal scene is coming up for auction. Thanks to its enduring allure, the backless gown designed by Jacqueline Durran is expected to sell for up to £120,000 ($161,000) when it goes under the hammer at Christie’s in London on December…