Add parental and photo authorizations + make health and vaccine sheet and motivation letter optional

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

participation/management/commands/export_results.py

@@ -1,6 +1,7 @@
 # Copyright (C) 2021 by Animath
 # SPDX-License-Identifier: GPL-3.0-or-later
 
+from django.conf import settings
 from django.core.management import BaseCommand
 from django.utils.formats import date_format
 from django.utils.translation import activate
@@ -9,7 +10,7 @@ from participation.models import Tournament
 
 class Command(BaseCommand):
     def handle(self, *args, **kwargs):
-        activate('fr')
+        activate(settings.PREFERRED_LANGUAGE_CODE)
 
         tournaments = Tournament.objects.order_by('-date_start', 'name')
         for tournament in tournaments: