message: make clippy happy, ResolverOpts initlalize with Default::default()
diff: @@ -13,11 +13,12 @@ pub async fn create_resolver(dns: Option<ResolverConfig>, _ipv6_first: bool) ->
  // Customized dns resolution
  match dns {
  Some(conf) => {
  - let mut resolver_opts = ResolverOpts::default();
  -
  + let resolver_opts = ResolverOpts {
  // Use Ipv4AndIpv6 strategy. Because Ipv4ThenIpv6 or Ipv6ThenIpv4 will return if the first query returned.
  // Since we want to use Happy Eyeballs to connnect to both IPv4 and IPv6 addresses, we need both A and AAAA records.
  - resolver_opts.ip_strategy = LookupIpStrategy::Ipv4AndIpv6;
  + ip_strategy: LookupIpStrategy::Ipv4AndIpv6,
  + ..ResolverOpts::default()
  + };
  trace!(
  "initializing DNS resolver with config {:?} opts {:?}",
  