SC-92157 readme add about gke-gcloud-auth-plugin

Author: nikopol

Changelog.md

@@ -3,7 +3,8 @@
 ## Version 1.2.0
 - Fix the cluster configuration's merging mechanism for string parameters
 - Remove support for legacy authorization (ABAC)
-- Authentication for `kubectl` command now relies on `gke-gcloud-auth-plugin` as this is the only supported mode starting with Kubernetes 1.26 (see [documentation](https://cloud.google.com/blog/products/containers-kubernetes/kubectl-auth-changes-in-gke))
+- Authentication for `kubectl` command now relies on `gke-gcloud-auth-plugin` as this is the only supported mode starting with Kubernetes 1.26 (see [documentation](https://cloud.google.com/blog/products/containers-kubernetes/kubectl-auth-changes-in-gke)). 
+/!\ if you're using a DSS version prior 11.4, you'll have to install `gke-gcloud-auth-plugin` manually (see the link above)
 
 ##  Version 1.1.5 - Feature and bugfix release
 - Fix action "Add node pool"