Maybe start the interview with asking the interviewer if they've ever worked with someone with a stutter before. Follow up by advising them that interviews are one of the most stressful situations for a person who stutters (or for most people), and that your starter is going to be particularly severe during the interview compared to how you normally are able to communicate. In other words, acknowledge the elephant in the room. If both you and the interviewer are dancing around the elephant, it's going to be hard for the two of you to connect.