A judge today dismissed the murder case against an Arizona woman who spent more than 20 years on death row in the 1989 killing of her 4-year-old son. Debra Jean Milke hugged her supporters and sobbed as she exited the Phoenix courtroom. Judge Rosa Mroz ended the case after prosecutors lost their last appeal last week. Milke was convicted of murder in 1990 in the death of her son, Christopher