Update ECK documentation for rotating credentials.

Signed-off-by: Michael Montgomery <[email protected]>

Author: naemono

deploy-manage/users-roles/cluster-or-deployment-auth/managed-credentials-eck.md

@@ -66,13 +66,17 @@ If you are using the `elastic` user credentials in your own applications, they w
 To regenerate all auto-generated credentials in a namespace, run the following command:
 
 ```sh
-kubectl delete secret -l eck.k8s.elastic.co/credentials=true
+kubectl delete secret -l eck.k8s.elastic.co/credentials=true,common.k8s.elastic.co/type!=kibana
 ```
 
 ::::{warning}
 This command regenerates auto-generated credentials of **all** {{stack}} applications in the namespace.
 ::::
 
+:::{note}
+Previous documentation suggested deleting all secrets with the label `eck.k8s.elastic.co/credentials=true`, which included the Kibana secret that contained encryption keys. Deletion of the Kibana config secret is not recommended.
+:::
+
 ## Creating custom users
 
 {{eck}} provides functionality to facilitate custom user creation through various authentication realms. You can create users using the native realm, file realm, or external authentication methods.
@@ -99,4 +103,4 @@ For more information, refer to [External authentication](/deploy-manage/users-ro
 
 ECK facilitates file-based role management through Kubernetes secrets containing the roles specification. Alternatively, you can use the Role management API or the Role management UI in {{kib}}.
 
-Refer to [Managing custom roles](/deploy-manage/users-roles/cluster-or-deployment-auth/defining-roles.md#managing-custom-roles) for details and ECK based examples.
+Refer to [Managing custom roles](/deploy-manage/users-roles/cluster-or-deployment-auth/defining-roles.md#managing-custom-roles) for details and ECK based examples.