Replace hardcoded DNS server values with configurable variables: - coredns_dns_server/coredns_extra_config for CoreDNS - dnsmasq_dns_server/dnsmasq_extra_args for dnsmasq This allows customization of DNS server settings and additional configuration options without modifying role templates. Change-Id: Ica54bc221a99e140a493a5f1c4cff94d6b9741d6 Signed-off-by: Arina Triandafilidi <atriandafilidi@mirantis.com>