Added nss-lookup target to avoid too early Prometheus start (before DNS)

If Prometheus started before DNS avail, HTTP SD will be suspended for a 10 mitues (by default)

Jun 15 23:46:45 prometheus.example.com prometheus[658]: ts=2024-06-15T16:46:45.209Z caller=refresh.go:71 level=error component="discovery manager scrape" discovery=http config=netdata msg="Unable to refresh target groups" err="Get \"https://netbox.example.com/api/plugins/prometheus-sd/virtual-machines/?status=active&has_primary_ip=true&tenant=prometheus&cf_prometheus_server=promethes.example.com\": dial tcp: lookup netbox.example.com: Temporary failure in name resolution"