chore: Delete related notifications if a conversation is deleted (#2592)

spec/models/conversation_spec.rb

@@ -399,4 +399,15 @@ RSpec.describe Conversation, type: :model do
       end
     end
   end
+
+  describe '#delete conversation' do
+    let!(:conversation) { create(:conversation) }
+
+    let!(:notification) { create(:notification, notification_type: 'conversation_creation', primary_actor: conversation) }
+
+    it 'delete associated notifications if conversation is deleted' do
+      conversation.destroy
+      expect { notification.reload }.to raise_error ActiveRecord::RecordNotFound
+    end
+  end
 end