fix issue with unspecific IPv6 addrs in conn IP tracking

Also, don't track loopback addrs.

score.go

@@ -761,7 +761,7 @@ func (ps *peerScore) getIPs(p peer.ID) []string {
 	}
 
 	conns := ps.host.Network().ConnsToPeer(p)
-	res := make([]string, 0, len(conns))
+	res := make([]string, 0, 1)
 	for _, c := range conns {
 		remote := c.RemoteMultiaddr()
 		ip, err := manet.ToIP(remote)
@@ -769,6 +769,12 @@ func (ps *peerScore) getIPs(p peer.ID) []string {
 			continue
 		}
 
+		// ignore those; loopback for unit testing and unspecific because gremlins in testground
+		// give us an unspecific IP6 conns everywhere!
+		if ip.IsUnspecified() || ip.IsLoopback() {
+			continue
+		}
+
 		if len(ip) == 4 {
 			// IPv4 address
 			ip4 := ip.String()