She’s given up acting – much to the delight of Britain’s hottest comedy duo. The Independent Hanging in pride of place over the dining room table in Kathy Burke’s north London home is a still from the set of Nil by Mouth, the acclaimed domestic-violence drama for which she deservedly won the Best Actress Award at the Cannes film festival in 1997. But there’s a surprise. The photo depicts the film’s director, Gary Oldman, leaning over to whisper something to her co-star Ray Winstone. Burke is not in the picture. It’s an apt image. For Burke, one of our most adored actresses, is now far happier to be absent from…