Pressure is mounting on the Hong Kong government to treat garbage from the 141 universal coronavirus testing centres across the city as clinical instead of domestic waste, as authorities reported about a tenth of the city’s 7.5 million people had signed up for the programme as of Wednesday.Appealing to citizens to take the test to track down invisible Covid-19 carriers, the government said about 798,000 people had registered for the programme as of 8pm. The free and voluntary scheme started on…