Detroit City Council has passed a watered-down "affordable" housing ordinance that will require some Detroit developers to provide cheaper rental units as the city undergoes a redevelopment that's pricing people out of key areas. The ordinance — which was already seen by affordability advocates as insufficient because it relies on the median income for the region, not the city of Detroit — was further weakened after council members, in a 5-3 vote, approved a last-minute amendment suggested by the Duggan administration.…