By Joice Alves LONDON (Reuters) -Sterling slipped on Friday, reversing earlier gains against the U.S. dollar, after Prime Minister Liz Truss and finance minister Kwasi Kwarteng met with Britain’s fiscal watchdog and confirmed markets would have to wait until Nov. 23 for new economic forecasts. Truss and Kwarteng refused to bow to demands to publish earlier forecasts of government growth plans and the impact of planned tax cuts which have led to turmoil in the financial markets this week. In a volatile session, the British currency edged 0.1% lower to $1.1112 at 1420 GMT after slipping as much …