Government departments and major corporations in Hong Kong have used a celebrity’s infidelity to warn against everything from corruption to not repairing run-down buildings, but not everyone has found it funny.On Tuesday, a 16-minute video of Andy Hui Chi-on, husband of superstar Sammi Cheng Sau-man, getting intimate with TVB actress Jacqueline Wong in the back of a car went viral.A tearful Hui later apologised at a press conference, which hundreds of thousands of people watched online. Wong…