By Laura Forsyth This weekend, the City will be transformed into a runner’s dream, as thousands lace up their shoes for the ultimate endurance test: the TCS London Marathon. As the big day is incoming – this year’s race falls onSunday, April 21 – runners and spectators need to know what to expect, with the event attracting participants from around the world. Participants may even recognise a few faces among the 50,000 participants – including TV presenter Romesh Ranganathan, Golden Globe-winning actor Ruth Wilson MBE, and Phil Dunster, of show Ted Lasso, who are all making their marathon debut…