Days after Harry Shearer announced he wasn’t returning to Fox’s The Simpsons for a 27th season, Nancy Cartwright and all her voices, including Bart Simpson, showed up at Deadline’s Cannes Film Festival studio at Nikki Beach’s Le Petit Bar at the Carlton Hotel. We asked her about Shearer’s sudden exit, to which she responded, “The only one who knows about it is Maggie and she’s not talkin!” It was Cartwright’s first visit to Cannes, but it wasn’t Bart’s first visit to…