Pull request 1933: upd-golibs

Squashed commit of the following:

commit 081d10e6909def3a075707e75dbd0c5f63f91903
Author: Ainar Garipov <A.Garipov@AdGuard.COM>
Date:   Thu Jul 20 14:17:01 2023 +0300

    aghnet: fix docs

commit 7433b72c0653cb33fe5ff810ae8a1346a6994f95
Author: Ainar Garipov <A.Garipov@AdGuard.COM>
Date:   Thu Jul 20 14:03:16 2023 +0300

    all: imp tests; upd golibs

internal/aghtest/aghtest.go

@@ -2,7 +2,9 @@
 package aghtest
 
 import (
+	"crypto/sha256"
 	"io"
+	"net"
 	"testing"
 
 	"github.com/AdguardTeam/golibs/log"
@@ -34,3 +36,10 @@ func ReplaceLogLevel(t testing.TB, l log.Level) {
 	t.Cleanup(func() { log.SetLevel(prev) })
 	log.SetLevel(l)
 }
+
+// HostToIPs is a helper that generates one IPv4 and one IPv6 address from host.
+func HostToIPs(host string) (ipv4, ipv6 net.IP) {
+	hash := sha256.Sum256([]byte(host))
+
+	return net.IP(hash[:4]), net.IP(hash[4:20])
+}