By Katie Wilson Simon Cowell was forced to pull out of filming some of the latest series of Britain’s Got Talent auditions at the last-minute – and now it’s been revealed why. The 64-year-old is worth a reported £475 million, but he has recently been spotted wearing a pair of orange tinted sunglasses that cost just £20 from Amazon. While some may have thought he was wearing them as a Bono-style fashion statement, there is another reason behind his new rock star look. Talent show judge Simon has suffered from crippling migraines ‘for years’ and found that spending long periods of time under bri…