hack/test-port-forwarding.pl: use single quotes to hostSocket on host side nc

Signed-off-by: Norio Nomura <[email protected]>

Author: norio-nomura

hack/test-port-forwarding.pl

@@ -174,7 +174,7 @@
 # Try to reach each listener from the host
 foreach my $test (@test) {
     next if $test->{host_port} == $sshLocalPort;
-    my $nc = $test->{host_socket} eq "" ? "nc -w 1 $test->{host_ip} $test->{host_port}" : "nc -w 1 -U $test->{host_socket}";
+    my $nc = $test->{host_socket} eq "" ? "nc -w 1 $test->{host_ip} $test->{host_port}" : "nc -w 1 -U '$test->{host_socket}'";
     open(my $netcat, "| $nc") or die "Can't run '$nc': $!";
     print $netcat "$test->{log_msg}\n";
     # Don't check for errors on close; macOS nc seems to return non-zero exit code even on success