update document about ubi suffix removal

Author: kvalliyurnatt

cmd/manager/main.go

@@ -322,7 +322,7 @@ func Command() *cobra.Command {
 cmd.Flags().Bool(
 operator.UBIOnlyFlag,
 false,
-fmt.Sprintf("Use only UBI container images to deploy Elastic Stack applications. UBI images are only available from 7.10.0 onward. Cannot be combined with %s", operator.ContainerSuffixFlag),
+fmt.Sprintf("Use only UBI container images to deploy Elastic Stack applications. UBI images are only available from 7.10.0 onward. Ignored from 9.x as default images are based on UBI. Cannot be combined with %s", operator.ContainerSuffixFlag),
 )
 cmd.Flags().Bool(
 operator.ValidateStorageClassFlag,

docs/operating-eck/operator-config.asciidoc

@@ -44,7 +44,7 @@ ECK can be configured using either command line flags or environment variables.
 |operator-namespace |"" |Namespace the operator runs in. Required.
 |password-hash-cache-size|5 x max-concurrent-reconciles|Sets the size of the password hash cache. Caching is disabled if explicitly set to 0 or any negative value.
 |set-default-security-context | auto-detect | Enables adding a default Pod Security Context to Elasticsearch Pods in Elasticsearch `8.0.0` and later. `fsGroup` is set to `1000` by default to match Elasticsearch container default UID. This behavior might not be appropriate for OpenShift and PSP-secured Kubernetes clusters, so it can be disabled.
-|ubi-only | false | Use only UBI container images to deploy Elastic Stack applications. UBI images are only available from 7.10.0 onward. Cannot be combined with `--container-suffix` flag.
+|ubi-only | false | Use only UBI container images to deploy Elastic Stack applications. UBI images are only available from 7.10.0 onward. Ignored from 9.x as default images are based on UBI. Cannot be combined with `--container-suffix` flag.
 |validate-storage-class | true | Specifies whether the operator should retrieve storage classes to verify volume expansion support. Can be disabled if cluster-wide storage class RBAC access is not available.
 |webhook-cert-dir |"{TempDir}/k8s-webhook-server/serving-certs" |Path to the directory that contains the webhook server key and certificate.
 |webhook-name |"elastic-webhook.k8s.elastic.co" |Name of the Kubernetes ValidatingWebhookConfiguration resource. Only used when `enable-webhook` is true.