Issue Title

ICMP Destination Unreachable identified as Timeout

General

Using .Net Core 2.1.301 on OSX 10.13.6

SendPingAsync seems to incorrectly report the reason for Ping failure.

var reply = await ping.SendPingAsync(Theip, timeout);
if (reply.Status == System.Net.NetworkInformation.IPStatus.Success)
{
Console.WriteLine("Success:" + Theip);
}
if (reply.Status == System.Net.NetworkInformation.IPStatus.DestinationHostUnreachable)
{
Console.WriteLine("Destination host unreachable:" + Theip);
}
if (reply.Status == System.Net.NetworkInformation.IPStatus.DestinationUnreachable)
{
Console.WriteLine("Destination unreachable:" + Theip);
}
if (reply.Status == System.Net.NetworkInformation.IPStatus.TimedOut) //Everything hits here ..
{
Console.WriteLine("Destination timedout:" + Theip);
}