By Grey Whitebloom Manchester United summer signing Leny Yoro has returned to first-team training after spending the opening three months of the season sidelined by injury. The £52m acquisition from Lille sustained a serious foot problem during United’s pre-season friendly against Arsenal on the club’s US tour. Yoro underwent surgery to correct the issue which has delayed his anticipated competitive debut. After posting a positive update on social media last month, the Frenchman has been spotted in full training for the first time since the season’s start. United’s official website confirmed t…