Sofia Richie cut a chic figure and she strolled hand-in-hand with her fiancé Elliot Grainge in Cannes on Wednesday. The model, 23, put on a leggy display in a black minidress featuring white stripes on its straps while keeping things casual with charcoal sandals. Emerging: Sofia Richie put on a leggy display in a black minidress while strolling hand-in-hand with …