fixed a typo in the machine set YAML

Author: jeana-redhat

modules/machineset-yaml-nutanix.adoc

@@ -99,7 +99,7 @@ endif::infra[]
             type: uuid
             uuid: <cluster_uuid>
           credentialsSecret:
-            name: nutanix-creds-secret
+            name: nutanix-credentials
           image:
             name: <infrastructure_id>-rhcos <8>
             type: name