Fix type error in announcement reaction update event payload (#12946)

app/workers/publish_announcement_reaction_worker.rb

@@ -10,7 +10,7 @@ class PublishAnnouncementReactionWorker
     reaction,  = announcement.announcement_reactions.where(name: name).group(:announcement_id, :name, :custom_emoji_id).select('name, custom_emoji_id, count(*) as count, false as me')
     reaction ||= announcement.announcement_reactions.new(name: name)
 
-    payload = InlineRenderer.render(reaction, nil, :reaction).tap { |h| h[:announcement_id] = announcement_id }
+    payload = InlineRenderer.render(reaction, nil, :reaction).tap { |h| h[:announcement_id] = announcement_id.to_s }
     payload = Oj.dump(event: :'announcement.reaction', payload: payload)
 
     Account.joins(:user).where('users.current_sign_in_at > ?', User::ACTIVE_DURATION.ago).find_each do |account|