software/kvm: only use frontend hostname for the promise

No need for the full URL here

software/kvm/buildout.hash.cfg

@@ -19,7 +19,7 @@ md5sum = f2b0f1ed27148504f220e06eaceff935
 
 [template-kvm]
 filename = instance-kvm.cfg.jinja2
-md5sum = 7429b71e6834ba8e016b1d8249aea8e8
+md5sum = 14b5ec1ee15c8d108c67cc3e9d87e6a6
 
 [template-kvm-cluster]
 filename = instance-kvm-cluster.cfg.jinja2.in

software/kvm/instance-kvm.cfg.jinja2

@@ -760,7 +760,7 @@ sla-instance_guid = ${slap-parameter:frontend-instance-guid}
 <= monitor-promise-base
 promise = check_url_available
 name = frontend_promise.py
-config-url = ${publish-connection-information:url}
+config-url = ${request-slave-frontend:connection-secure_access}
 
 {% if additional_frontend %}
 [request-slave-frontend-additional]