feat: add management command to delete accounts

This is needed to support development and staging activities, so that we
can remove and re-populate test data for use in user acceptance testing.

activate_account/management/commands/delete_all_account_data.py

+from pprint import pprint
+
+from django.core.management.base import BaseCommand
+
+from activate_account.models import Account
+
+
+class Command(BaseCommand):
+    help = "Deletes account data in databases"
+
+    def handle(self, *args, **options):
+        account_count = Account.objects.all().count()
+        if account_count == 0:
+            self.stdout.write(self.style.SUCCESS("No accounts to delete."))
+            return
+
+        self.stdout.write(self.style.WARNING("Deleting account data in database..."))
+        self.stdout.write(f"There are currently {account_count} accounts in the database.")
+        self.stdout.write(self.style.WARNING("Are you sure you want to continue?"))
+
+        result = input("Enter 'yes' to delete all data: ")
+        if result.lower() == "yes":
+            pprint(Account.objects.all().delete())
+        else:
+            self.stdout.write("Not deleting any objects.")