Tori Spelling calledDean McDermottto tell her husband of nearly 20 years that she filed for divorce — and her podcast fans listened in on their private conversation, RadarOnline.com has learned. “Oh, s—. He’s at work right now. This sucks,” the Beverly Hills, 90210 star, 50, said as she dialed his number. Spelling said she “hate[d] to do this to” her ex, 57, “in the middle of going to work and everything.” When McDermott picked up the phone, she announced, “They’ve done it. It’s the formality. It’s just the one sheet you check off, and next you’ll have to sign it.” FYI — she did not air McDe…