docs: changes quick start docs to use templating

Author: faiq

docs/content/getting-started/create-cluster/nutanix.md

@@ -29,7 +29,8 @@ export CONTROL_PLANE_ENDPOINT_IP=<value> \
        DOCKER_HUB_USERNAME=<value> \
        NUTANIX_ENDPOINT=<value> \
        NUTANIX_INSECURE=<value> \
-       NUTANIX_MACHINE_TEMPLATE_IMAGE_NAME=<value> \
+       NUTANIX_MACHINE_TEMPLATE_BASE_OS=<value> \
+       NUTANIX_MACHINE_TEMPLATE_LOOKUP_FORMAT=<value> \
        NUTANIX_PASSWORD=<value> \
        NUTANIX_PORT=<value> \
        NUTANIX_PRISM_ELEMENT_CLUSTER_NAME=<value> \