Katy Perry (42) has appeared in public for the first time since the conviction of her ex-husband Russell Brand (51). On Wednesday evening, the singer was dining with Justin Trudeau (54) and some friends at the celebrity restaurant E. Baldi in Beverly Hills. When leaving the restaurant, Katy and the former Canadian Prime Minister made a familiar impression. On the recordings that TMZ are available, in the evening, the two can be seen hand in hand…