fix: Conversation assignment notification title (#9071)

app/models/notification.rb

@@ -106,8 +106,10 @@ class Notification < ApplicationRecord
     case notification_type
     when 'conversation_creation'
       message_body(conversation.messages.first)
-    when 'assigned_conversation_new_message', 'participating_conversation_new_message', 'conversation_assignment', 'conversation_mention'
+    when 'assigned_conversation_new_message', 'participating_conversation_new_message', 'conversation_mention'
       message_body(secondary_actor)
+    when 'conversation_assignment'
+      message_body(conversation.messages.incoming.last)
     else
       ''
     end

spec/models/notification_spec.rb

@@ -76,6 +76,13 @@ has been assigned to you"
       expect(notification.push_message_body).to eq "#{message.sender.name}: #{message.content.truncate_words(10)}"
     end
 
+    it 'returns appropriate body suited for the notification type conversation_assignment' do
+      conversation = create(:conversation)
+      message = create(:message, sender: create(:user), content: Faker::Lorem.paragraphs(number: 2), conversation: conversation)
+      notification = create(:notification, notification_type: 'conversation_assignment', primary_actor: conversation, secondary_actor: message)
+      expect(notification.push_message_body).to eq "#{message.sender.name}: #{message.content.truncate_words(10)}"
+    end
+
     it 'returns appropriate body suited for the notification type assigned_conversation_new_message' do
       conversation = create(:conversation)
       message = create(:message, sender: create(:user), content: Faker::Lorem.paragraphs(number: 2), conversation: conversation)