Industry leaders in Hong Kong fear the catering sector is on the brink of collapse as social-distancing rules remain stringent despite a slight easing of measures amid a downward trend in Covid-19 infections.They called for a further relaxation of the rules after the government announced on Tuesday that restaurant dine-in services would be allowed until 9pm, rather than 6pm, from Friday but bars and pubs would remain closed.There were 19 new coronavirus cases on Tuesday, and the number of…