Singer Linda Perry revealed she secretly battled b—— cancer in 2021. The 59-year-old was diagnosed with the disease and underwent a double mastectomy at the time, she revealed in a new interview with People. “I feel so lucky because there’s so many women that don’t get that opportunity,” she said. Perry realized she had cancer when she was preparing for an elective b—— reduction surgery, she said in her new documentary Linda Perry: Let It Die Here, which premiered at the Tribeca Film Festival in New York City on June 6. After going under the knife, doctors discovered she had triple neg…