Does My Spy Have a Post-Credit Scene?

Yes, there are extra scenes during, or after, the end credits of My Spy.

Stylized scenes from the movie are shown for about the first 2 minutes of the credits. At the very end of the stylized credits there's a 5 second clip of Dave Bautista dancing and waving goodbye as he gets in an elevator. (I don't think it's worth sticking around for just that tiny extra clip.)

After that there's only scrolling credits for the next 6 minutes or so.

The credits run for approximately 8 minutes.