Usually, a multiple choice test is called un QCM (Questionnaire à Choix Multiple).

If this test is not graded, we will use the adjective blanc like in “balle à blanc” (blank bullet).

Thus, you could say “un QCM blanc”.

You can also say: QCM d’auto-évaluation

When I was in high school, my teachers would talk about a similar exercise as a test formatif or examen formatif, since it helped you learn in an examination situation.

I’m not exactly sure if it was the same thing you’re describing though. In my situation, the tests were graded, but they did not count in the students final grades. They were literally practice exams. Students knew what they were before doing them, so no panic, but all the elements would be that of an actual exam so that the students could know how they would perform if that had been the real exam and could adjust their studying accordingly.