By David Milliken and Andy Bruce LONDON (Reuters) – The Bank of England raised interest rates by the most since 1989 on Thursday but it also warned that Britain faced a long recession and told investors borrowing costs were likely to go up by less than they expect. The BoE increased Bank Rate to 3% from 2.25% even as it said Britain’s economy might not grow for another two years, a slump longer than during the 2008-09 financial crisis. The pound fell sharply and was down about 2% against the U.S. dollar at 1315 GMT, touching its lowest since mid-October when Britain was in a political crisis t…