feat: Add option to mask e-mails and phone numbers

This is a prerequisite to do tests on DEv and UAT systems

src/fellchensammlung/management/commands/mask_contact_data.py

@@ -0,0 +1,13 @@
+from django.core.management import BaseCommand
+from fellchensammlung.tools.admin import mask_organization_contact_data
+
+
+class Command(BaseCommand):
+    help = 'Mask e-mail addresses and phone numbers of organizations for testing purposes.'
+
+    def add_arguments(self, parser):
+        parser.add_argument("domain", type=str)
+
+    def handle(self, *args, **options):
+        domain = options["domain"]
+        mask_organization_contact_data(domain)