By Kirstin Ridley LONDON (Reuters) -Failings at Britain’s Serious Fraud Office (SFO) were in the spotlight on Thursday as a government-ordered review laid bare the agency’s missteps in a high-profile bribery case as a London court simultaneously quashed a third criminal conviction. Former High Court judge David Calvert-Smith, appointed to review the agency after its Unaoil bribery case started unravelling last year, said serious problems at the top of the SFO must never be allowed to reoccur. Piling fresh pressure on SFO Director Lisa Osofsky, they included a failure to properly record meeting…