Update docs/en/stack/security/authentication/built-in-users.asciidoc

Co-Authored-By: lcawl <[email protected]>

Author: tvernum

docs/en/stack/security/authentication/built-in-users.asciidoc

@@ -21,7 +21,7 @@ storing monitoring information in {es}. It has the `remote_monitoring_agent` and
 [[built-in-user-explanation]]
 ==== How the built-in users work
 These built-in users are stored in a special `.security` index, which is managed
-by the {security-features}. If a built-in user is disabled or its password
+by {es}. If a built-in user is disabled or its password
 changes, the change is automatically reflected on each node in the cluster. If
 your `.security` index is deleted or restored from a snapshot, however, any
 changes you have applied are lost.