Merge branch...

Merge branch '65386-docs-add-elasticsearch-troubleshooting-to-administrator-troubleshooting-section' into 'master'

Docs-Add ElasticSearch Troubleshooting

Closes #65386

See merge request gitlab-org/gitlab-ce!31343

doc/administration/index.md

@@ -187,3 +187,4 @@ Learn how to install, configure, update, and maintain your GitLab instance.
 - [Sidekiq Troubleshooting](troubleshooting/sidekiq.md): Debug when Sidekiq appears hung and is not processing jobs.
 - Useful [diagnostics tools](troubleshooting/diagnostics_tools.md) that are sometimes used by the GitLab
   Support team.
+- [Troubleshooting ElasticSearch](troubleshooting/elasticsearch.md): Tips to troubleshoot ElasticSearch.