Update logstash_conf.rb

Current errorous generation:

file {
  codec => [multiline ['negate', true, 'pattern', '^\[\#\|\d{4}', 'patterns_dir',  '/opt/logstash/agent/etc/patterns', 'what' , 'previous']]
 'format' => 'plain'
 'path' => '/var/log/glassfish/greyhound/server.log'
 'type' => 'glassfish'
}

With this fix changed to:

file {
  codec => multiline {
    'negate' => true
    'pattern' => '^[#|\d{4}'
    'patterns_dir' => '/opt/logstash/agent/etc/patterns'
    'what' => 'previous'
  }
  'format' => 'plain'
  'path' => '/var/log/glassfish/greyhound/server.log'
  'type' => 'glassfish'
}