add deprecation notes

Author: tejal29

mmv1/third_party/terraform/website/docs/guides/version_6_upgrade.html.markdown

@@ -318,6 +318,12 @@ on the resource through Terraform and the default labels configured on the provi
 * The new output-only `effective_labels` field lists all of labels present on the resource
 in GCP, including the labels configured through Terraform, the system, and other clients.
 
+## Resource: `google_workstations_workstation_config`
+
+### Disable SSH to root VM is set to true by default for workstation config.
+
+* `disableSSH` field is set to true when creating configs. To enable SSH, please set `disableSSH` to false.
+
 ## Removals
 
 ### Resource: `google_identity_platform_project_default_config` is now removed