This resignation letter lets management know that you don't intend to participate in an exit interview.
Dear Mr./Ms. Bossname,
I am submitting my resignation, effective in two weeks’ time.
While I recognize that it is customary at this company to participate in an exit interview, I really don’t have any specific insights to add, and I prefer to focus on easing in the transition and wrapping up my pending projects. I will certainly let you know if I think of any useful feedback in the next couple of weeks.
Thank you for the opportunity to be part of the company team.