CHICAGO — Mayor Brandon Johnson will delay enforcing his 60-day migrant shelter limit policy for the first group of asylum-seekers due to leave the system next week, his administration announced Friday as heavy snowfall and low wind chills pummeled the city. The group of about 50 migrant shelter residents who have been in the system since 2022 and had been required to leave by Tuesday will now get to stay through “at least” Jan. 22, said Brandie Knazze, commissioner of the Department of Family and Support Services. The same goes for another 600 residents who entered the shelter system after th…