murano internal authentication needs /v3

Missing [murano_auth] with auth_uri ending in '/v3' leads to
keystone authentication failures - murano uses old v2 keystone.

Change-Id: I41846ac4fa78da90e02d91e8d1cec7405178f7df
Closes-Bug: #1753480

ansible/roles/murano/templates/murano.conf.j2

@@ -31,6 +31,9 @@ memcache_security_strategy = ENCRYPT
 memcache_secret_key = {{ memcache_secret_key }}
 memcached_servers = {% for host in groups['memcached'] %}{{ hostvars[host]['ansible_' + hostvars[host]['api_interface']]['ipv4']['address'] }}:{{ memcached_port }}{% if not loop.last %},{% endif %}{% endfor %}
 
+[murano_auth]
+auth_uri = {{ internal_protocol }}://{{ kolla_internal_fqdn }}:{{ keystone_public_port }}/v3
+
 [murano]
 url = {{ internal_protocol }}://{{ kolla_internal_fqdn }}:{{ murano_api_port }}
 api_workers = {{ openstack_service_workers }}