LONDON (Reuters) - German online bank N26 has become the first European lender to quit Britain and close all UK accounts because it will no longer be able to use its banking licence in the country after Brexit.The Berlin-based company, which launched in Britain in 2018, said last year it was adding around 1,000 British customers a day. It currently has 5 million users across Europe.At the time of its launch, Chief Executive Valentin Stalf described the UK as a "no brainer" for the neo-bank,..