Fix empty home feed before first follow has finished processing (#16152)

Change queue of merge worker from pull to default

app/workers/merge_worker.rb

@@ -3,11 +3,11 @@
 class MergeWorker
   include Sidekiq::Worker
 
-  sidekiq_options queue: 'pull'
-
   def perform(from_account_id, into_account_id)
     FeedManager.instance.merge_into_home(Account.find(from_account_id), Account.find(into_account_id))
   rescue ActiveRecord::RecordNotFound
     true
+  ensure
+    Redis.current.del("account:#{into_account_id}:regeneration")
   end
 end