quote user display name for email name-addr format (#1171)

ephios/core/services/notifications/backends.py

@@ -1,6 +1,7 @@
 import logging
 import smtplib
 import traceback
+from email.utils import formataddr
 
 from django.conf import settings
 from django.core.mail import mail_admins
@@ -94,7 +95,7 @@ def can_send(cls, notification):
     @classmethod
     def _get_mailaddress(cls, notification):
         if notification.user:
-            return f"{notification.user.get_full_name()} <{notification.user.email}>"
+            return formataddr((notification.user.get_full_name(), notification.user.email))
         return notification.data.get("email")
 
     @classmethod