By Michael Holden and Alistair Smout LONDON (Reuters) -Britain’s new finance minister Jeremy Hunt said on Saturday some taxes would go up and tough spending decisions were needed, saying Prime Minister Liz Truss had made mistakes as she battles to keep her job just over a month into her term. In an attempt to appease financial markets that have been in turmoil for three weeks, Truss fired Kwasi Kwarteng as her chancellor of the exchequer on Friday and scrapped parts of their controversial economic package. With opinion poll ratings dire for both the ruling Conservative Party and the prime mini…