Hong Kong’s embattled leader has shrugged off claims that the unpopularity of her administration is an impediment to the city’s mass testing scheme for Covid-19, hitting back at a union formed by public health workers calling for a boycott.“I don’t think it has something to do with the government’s popularity” Chief Executive Carrie Lam Cheng Yuet-ngor said on Tuesday during her weekly press briefing, before pointing the finger back at “people” who lacked understanding of the scheme and tried…