INTERVIEW: As the ‘EastEnders’ legend voices an elderly feline in Ricky Gervais’s outrageous new animated sitcom ‘Alley Cats’, she speaks to Adam White about flying to Malaga to ‘drink red wine and smoke fags’ with June Brown, her fitness DVD regrets, and the origins of that infamous ‘SEX’ necklace she wore to Dean Gaffney’s birthday party