Debi Mazar claims the set of “Entourage” became “toxic” for her after she gained weight following the birth of her second daughter. “In the third season, the set was a testosterone-fueled environment,” Mazar told the Sunday Times. “I’m tough, but it got toxic towards the end for me,” she claimed. The actress, who played publicist Shauna Roberts throughout the show’s eight-season run, recalled the alleged reaction from her co-workers when after returned to set following her maternity leave. “I’d had my second baby and they didn’t like that I got fat, even though I got skinny again,” Mazer claimed, without specifically naming who made her…