Show will have final performance in September after taking more than £120m at box office in LondonOver the past 15 years it has featured actors including Brooke Shields, Christie Brinkley and David Hasselhoff and become the West End's longest-running revival, but the curtain is finally coming down on Chicago in London's theatre district.Barry Weissler, who has produced the musical along with his wife Fran in locat…