LONDON — Prince Harry entered the witness box on Wednesday in his final legal showdown with Britain's tabloid media. It is the estranged royal's second time testifying in court, and comes as he leads a group of seven high-profile claimants, including Elton John and actors Elizabeth Hurley and Sadie Frost in a privacy lawsuit against one of Britain's biggest news organizations, Associated Newspapers Limited (ANL). They have accused the publisher of the Daily Mail and The Mail on Sunday