dns: Resolve DNS address to multiple IP addresses to make dialing more robust

[lexnv]

The current DNS implementation extracts the first IP address from the DNS translation.
In practice, this works most of the time, however the DNS translation can produce multiple IP addresses.

litep2p/src/transport/common/listener.rs

Lines 87 to 90 in a68b713

	let lookup =
	match TokioAsyncResolver::tokio(ResolverConfig::default(), ResolverOpts::default())
	.lookup_ip(url.clone())
	.await

Returns a list of resolved IP addresses from the DNS component.

This helps improve the dialing attempts made by TCP and WebSocket transports.
When the transport fails to dial the first IP, it can move on to the next one until addresses are exhausted (or limit reached).

This is the code where we take into account the first address we find:

litep2p/src/transport/common/listener.rs

Lines 105 to 118 in a68b713

	let Some(ip) = lookup.iter().find(|ip| match dns_type {
	DnsType::Dns => true,
	DnsType::Dns4 => ip.is_ipv4(),
	DnsType::Dns6 => ip.is_ipv6(),
	}) else {
	tracing::debug!(
	target: LOG_TARGET,
	"Multiaddr DNS type does not match IP version `{}`",
	url
	);
	return Err(DnsError::IpVersionMismatch);
	};
	Ok(SocketAddr::new(ip, port))