move import later because django 3.2

src/teams/signal_handlers.py

@@ -1,6 +1,5 @@
 import logging
 
-from .email import add_new_membership_email
 
 logger = logging.getLogger("bornhack.%s" % __name__)
 
@@ -12,6 +11,8 @@ def teammember_saved(sender, instance, created, **kwargs):
     # if this is a new unapproved teammember send a mail to team responsibles
     if created and not instance.approved:
         # call the mail sending function
+        # late import to please django 3.2 or "django.core.exceptions.AppRegistryNotReady: Apps aren't loaded yet."
+        from .email import add_new_membership_email
         if not add_new_membership_email(instance):
             logger.error("Error adding email to outgoing queue")