add missing varaiable declaration

Author: GregWhiteyBialas

etc/kayobe/stackhpc-monitoring.yml

@@ -21,6 +21,9 @@ stackhpc_enable_os_capacity: true
 stackhpc_os_capacity_openstack_verify: true
 # Redfish exporter
 
+# Whether the redfish exporter is enabled.
+stackhpc_enable_redfish_exporter: false
+
 # Credentials
 redfish_exporter_default_username: "{{ ipmi_admin_user }}"
 redfish_exporter_default_password: "{{ ipmi_admin_password }}"