Fix error during Grafana container restart
Fix error during Grafana container restart

grafana_ini file used in test condition doesn't exists,
use grafana_conf file instead.

Change-Id: Id5dca94aed98b0d6cf6c4f841e7380f8b8154416
Closes-Bug: #1673932

dardelean/kolla-ansible,dardelean/kolla-ansible,dardelean/kolla-ansible