By Mia O’Hare Fern Britton savagely hit out at Gary Barlow in a candid chat with Sharon Osbourne. The former This Morning host recalled working with the Take That singer while chatting in the Celebrity Big Brother house. She told her housemates: “Gary, he wrote the music for Calendar Girls The Musical.” Sharon Osbourne, who left the house on Tuesday night, said: “Oh, I remember. Yes – of course I do.” Fern added: “We went out on tour. He had no personality and he had to have this particular water and this particular teabags and particular blah blah…never touched any of it, of course.” Sharon…