A second financial ratings agency has downgraded Chicago Public Schools’ debt rating to junk status, reinforcing Wall Street’s dim view of the district’s finances. Fitch Ratings on Monday downgraded billions of school board bonds to its “BB+” ranking, which it said reflected the “limited progress” CPS has made to address a vast budget gap as well as the district’s meager cash reserves. Fitch said those reserves are likely to be extinguished by next year. District officials have announced $200 million in spending cuts. Fitch said the district also will require “a combination of tax increases, contributions from the state and...