emails: Make missed message email come from 'Zulip Missed Messages.'

zerver/lib/notifications.py

@@ -320,7 +320,8 @@ def do_send_missedmessage_events_reply_in_zulip(user_profile, missed_messages, m
         'realm_str': user_profile.realm.name,
     })
 
-    from_name, from_address = None, None
+    from_name = "Zulip Missed Messages"  # type: Text
+    from_address = FromAddress.NOREPLY
     if len(senders) == 1 and settings.SEND_MISSED_MESSAGE_EMAILS_AS_USER:
         # If this setting is enabled, you can reply to the Zulip
         # missed message emails directly back to the original sender.

zerver/tests/test_notifications.py

@@ -48,7 +48,7 @@ class TestMissedMessages(ZulipTestCase):
         else:
             reply_to_emails = ["noreply@zulip.example.com"]
         msg = mail.outbox[0]
-        from_email = formataddr(("Zulip", FromAddress.NOREPLY))
+        from_email = formataddr(("Zulip Missed Messages", FromAddress.NOREPLY))
         self.assertEqual(len(mail.outbox), 1)
         if send_as_user:
             from_email = '"%s" <%s>' % (othello.full_name, othello.email)