DETROIT — Comedian Pete Davidson is saying he was high on ketamine at the funeral for the Queen of Soul, Aretha Franklin. In his new Netflix special “Turbo Fonzarelli,” released Tuesday, Davidson talks about his past drug use and the shame he now feels because of it. “It’s embarrassing when you’re not on ketamine anymore, though,” the “Saturday Night Alive” alum says during the special, which was taped in November. “I’m embarrassed. I was out and about like that. That’s not cool, you know? I was at funerals like that. That’s (messed) up, right? I was at Aretha Franklin’s funeral like that. Yea…