PHILADELPHIA — The ranks of Republicans rejecting State Sen. Doug Mastriano, their party’s nominee for governor in Pennsylvania, grew this week as a former national security Cabinet member and a former Trump administration lawyer endorsed the Democratic nominee, state Attorney General Josh Shapiro. Michael Chertoff, who served as secretary for the U.S. Department of Homeland Security from 2005 to 2009 under then-President George W. Bush, said he considers Mastriano “a real threat to the values of the rule of law” because Mastriano has pushed lies about the 2020 presidential election and was pr...