Hong Kong is expecting about 26 new Covid-19 cases on Saturday, according to a source, extending the city’s run of under 100 daily infections to a 20th day.On Friday, health officials reported 27 cases, taking the official tally to 4,631, with 75 related deaths. Saturday’s confirmed number of cases will be announced later in the afternoon by the authorities.Meanwhile, Secretary for Food and Health Sophia Chan Siu-chee told a morning radio show that preparations for the citywide voluntary Covid…