FIX: Can't update status_type of topic timers.

https://meta.discourse.org/t/topic-timers-internal-error-500/64805

spec/models/topic_spec.rb

@@ -470,7 +470,7 @@ describe Topic do
 
             expect(notification.user).to eq(user)
             expect(notification.topic).to eq(topic)
-            
+
             expect(notification.notification_type)
               .to eq(Notification.types[:invited_to_private_message])
           end
@@ -1267,6 +1267,16 @@ describe Topic do
       end
     end
 
+    it 'should allow status_type to be updated' do
+      Timecop.freeze do
+        topic_timer = closing_topic.set_or_create_timer(
+          TopicTimer.types[:publish_to_category], 72, by_user: admin
+        )
+
+        expect(topic_timer.execute_at).to eq(3.days.from_now)
+      end
+    end
+
     it "does not update topic's topic status created_at it was already set to close" do
       expect{
         closing_topic.set_or_create_timer(TopicTimer.types[:close], 14)

spec/models/topic_timer_spec.rb

@@ -260,7 +260,8 @@ RSpec.describe TopicTimer, type: :model do
       open_topic_timer = Fabricate(:topic_timer,
         status_type: described_class.types[:open],
         execute_at: Time.zone.now - 1.hour,
-        created_at: Time.zone.now - 2.hour
+        created_at: Time.zone.now - 2.hour,
+        topic: Fabricate(:topic, closed: true)
       )
 
       Fabricate(:topic_timer)