Minor, added this PR number to changelog

Author: andsel

CHANGELOG.md

@@ -1,5 +1,5 @@
 ## Unreleased
- - Feature: deprecates the `failure_type_logging_whitelist` configuration option, renaming it `log_silenced_errors` [#n](https://github.com/logstash-plugins/logstash-output-elasticsearch/pull/n)
+ - Feature: deprecates the `failure_type_logging_whitelist` configuration option, renaming it `log_silenced_errors` [#1068](https://github.com/logstash-plugins/logstash-output-elasticsearch/pull/1068)
 
 ## 11.6.0
  - Added support for `ca_trusted_fingerprint` when run on Logstash 8.3+ [#1074](https://github.com/logstash-plugins/logstash-output-elasticsearch/pull/1074)