use chunk_id in path

According to your documentation it is allowed to use

path "/log/access/%Y%m%d/#{Socket.gethostname}.${chunk_id}.log"

In my case

path "/raw/syslog/logdate=%Y%m%d/loghour=%H/#{Socket.gethostname}.${chunk_id}.journald.log"

failed to communicate hdfs cluster, path: /raw/syslog/logdate=20190625/loghour=07/fluentd3.2019-06-25 08:11:10 +0000 [warn]: #10 ${chunk_id} is not allowed in this plugin. Pass Chunk instead of metadata in extract_placeholders's 2nd argument.journald.log.gz

It is acceptable to use worker_id as https://github.com/fluent/fluentd/issues/1473 in my case only.