Add back call to execute_hooks

app/models/concerns/issuable.rb

@@ -270,6 +270,8 @@ module Issuable
 
   def to_hook_data(user, old_associations: {})
     changes = previous_changes
+
+    if old_associations
       old_labels = old_associations.fetch(:labels, [])
       old_assignees = old_associations.fetch(:assignees, [])
 
@@ -292,6 +294,7 @@ module Issuable
           changes[:total_time_spent] = [old_total_time_spent, total_time_spent]
         end
       end
+    end
 
     Gitlab::HookData::IssuableBuilder.new(self).build(user: user, changes: changes)
   end

app/services/issuable_base_service.rb

@@ -237,7 +237,6 @@ class IssuableBaseService < BaseService
 
   def update_task(issuable)
     filter_params(issuable)
-    # old_associations = associations_before_update(issuable)
 
     if issuable.changed? || params.present?
       issuable.assign_attributes(params.merge(updated_by: current_user))
@@ -252,12 +251,9 @@ class IssuableBaseService < BaseService
         end
 
         handle_task_changes(issuable)
-
         invalidate_cache_counts(issuable, users: issuable.assignees.to_a)
-
         after_update(issuable)
-
-        # execute_hooks(issuable, 'update', old_associations: old_associations)
+        execute_hooks(issuable, 'update', old_associations: nil)
       end
     end