Fix problems export

Signed-off-by: Emmy D'Anello <emmy.danello@animath.fr>

apps/participation/management/commands/export_solutions.py

@@ -43,11 +43,11 @@ class Command(BaseCommand):
         ]
 
         for problem_id, problem_name in enumerate(PROBLEMS):
-            dir_name = f"Problème n°{problem_id} : {problem_name}"
+            dir_name = f"Problème n°{problem_id + 1} : {problem_name}"
             problem_dir = base_dir / dir_name
             if not problem_dir.is_dir():
                 problem_dir.mkdir()
-            self.handle_problem(problem_id, problem_dir)
+            self.handle_problem(problem_id + 1, problem_dir)
 
     def handle_tournament(self, tournament, base_dir):
         name = tournament.name