Default heal_instance_info_cache_interval=-1

The supported networking backends expected to work without the periodic
healing of the cache in nova. So turning the periodic healing off can be
done to gain performance.

Resolves: OSPRH-10744

templates/nova.conf

@@ -50,6 +50,7 @@ cert={{.SSLCertificateFile}}
 key={{.SSLCertificateKeyFile}}
 {{end}}
 {{end}}
+heal_instance_info_cache_interval=-1
 
 [oslo_concurrency]
 lock_path = /var/lib/nova/tmp