By City A.M. Editorial This election is a chance for Rishi Sunak to grab the nation’s ear. But he’ll have to say something more compelling than he’s managed so far to keep Britain’s attention. The best that can be said for Rishi Sunak’s speech outside 10 Downing Street yesterday is that unlike his predecessor but two, Theresa May, the stage didn’t fall down. Standing sodden in the rain, looking every bit the wally without a brolly, he looked a man who knew he was facing the fight of his life – and who didn’t feel as if the gods were on his side. In truth, he had to take the plunge at some poin…