TestHostIsResolved test fails if running with a public IPv6

[nalepae]

Describe the bug

TestHostIsResolved test is failing if running with a public IPv6.

Has this worked before in a previous version?

Probably not.

Error

--- FAIL: TestHostIsResolved (0.01s)
    /Users/manu/OffchainLabs/prysm/beacon-chain/p2p/assertions.go:37: discovery_test.go:237 Did not resolve to expected IP, want: 93.184.216.34 (string), got: 192.168.1.30 (string)

Platform(s)

Mac (Apple Silicon)

What version of Prysm are you running? (Which release)

develop

Anything else relevant (validator index / public key)?

Probable root cause:

➜  ~ host example.org
example.org has address 93.184.216.34
example.org has IPv6 address 2606:2800:220:1:248:1893:25c8:1946

https://github.com/prysmaticlabs/prysm/blob/develop/beacon-chain/p2p/discovery.go#L191

ips, err := net.LookupIP(host)

When running with a public IPv6 returns the following ips:

• The first one, once stringified, is equal to 2606:2800:220:1:248:1893:25c8:1946 (the public IPv6 address of example.org).
• The second one, once stringified, is equal to 93.184.216.34 (the public IPv4 address of example.org).

==> ips contains two elements. The first one is IPv6, the second one is IPv4.

When running with a public IPv4, the order of ips is reversed. First IPv4, then IPv6.