The Duchess of Cambridge rocked the Prince’s Trust concert last night and again she chose a High Street fave for her dress. She wore a black and white lace mini dress from Spanish giant Zara, and teamed it with a thick black belt and a Ralph Lauren Jacket, which I believe she wore with another Zara dress as part of her going away outfit after the Royal Wedding. This dress has raised a few eyebrows, as it was far shorter than any outfit she has worn since her wedding, but this was a concert, and so teamed with black tights, this was as close to doing ‘Rock chick’ as Kate…