delayed jobs: drop failed jobs email alert.

Usually when jobs aren't working it's not because the jobs themselves
are failing, it's because the workers crashed and aren't processing jobs
at all.

app/logical/delayed_job_error_checker.rb

@@ -1,22 +0,0 @@
-#!/usr/bin/env ruby
-
-require 'mail'
-
-class DelayedJobErrorChecker
-  def check!
-    errors = Delayed::Job.where("last_error is not null").limit(100).pluck(:last_error).map {|x| x[0..100]}
-    if errors.size == 100
-      mail = Mail.new do
-        from Danbooru.config.contact_email
-        to Danbooru.config.contact_email
-        CurrentUser.as_system do
-          subject "[#{Danbooru.config.app_name}] Delayed job error count at #{errors}"
-        end
-        body errors.uniq.join("\n")
-      end
-      mail.delivery_method :sendmail
-      mail.deliver
-    end
-  end
-end
-

app/logical/maintenance.rb

@@ -3,7 +3,6 @@ module Maintenance
 
   def hourly
     UploadErrorChecker.new.check!
-    DelayedJobErrorChecker.new.check!
   rescue Exception => exception
     rescue_exception(exception)
   end