Add matderidder

Liste_etudiants.csv

@@ -101,7 +101,7 @@ jean-baptiste.dellafaille@student.uclouvain.be,"della Faille d'Huysse, Jean-Bapt
 antoine.demblon@student.uclouvain.be,"Demblon, Antoine",Non
 axel.denis@student.uclouvain.be,"Denis, Axel",Non
 theo.denis@student.uclouvain.be,"Denis, Théo",Non
-mathieu.deridder@student.uclouvain.be,"Deridder, Mathieu",Non
+mathieu.deridder@student.uclouvain.be,"Deridder, Mathieu",Oui
 lois.dermine@student.uclouvain.be,"Dermine, Loïs",Non
 brieuc.derosen@student.uclouvain.be,"de Rosen de Borgharen, Brieuc",Non
 sacha.descampe@student.uclouvain.be,"Descampe, Sacha",Non