PARIS– Gaumont and LGM, who partnered on Cesar-winning comedy hit “My, Myself and Mum,” are back on board with “We Were Young,” a ensemble dramedy by Philippe Guillard (“Jo’s Boy”). Co-producing and handling international sales, Gaumont will unveil the project at the Unifrance Rendez-Vous in Paris. It toplines Kad Merad (“The Chorus”), Benoît Magimel (“Little White Lies”), Charles Berling (“What’s in...