Add note about toggle of Elastic Search pause

Feature added via https://gitlab.com/gitlab-org/gitlab/-/merge_requests/34069 makes automatic changes to the
pause settings internally
which shows up on the UI too, even if a user did not directly perform
the change

doc/integration/elasticsearch.md

@@ -311,10 +311,11 @@ used by the GitLab Advanced Search integration.
 
 In the **Admin Area > Settings > General > Advanced Search** section, select the
 **Pause Elasticsearch Indexing** setting, and then save your change.
-
 With this, all updates that should happen on your Elasticsearch index will be
 buffered and caught up once unpaused.
 
+The indexing will also be automatically paused when the [**Trigger cluster reindexing**](#trigger-the-reindex-via-the-advanced-search-administration) button is used, and unpaused when the reindexing completes or aborts.
+
 ### Setup
 
 NOTE: