test: discard data received by client

This test was timing out after update to OpenSSL-1.1.1e.

PR-URL: #32328
Fixes: #32210
Reviewed-By: Sam Roberts <vieuxtech@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>

test/sequential/test-tls-psk-client.js

@@ -37,6 +37,7 @@ const timeout = setTimeout(() => cleanUp('Timeouted'), 5000);
 
 function waitForPort(port, cb) {
   const socket = net.connect(common.PORT, () => {
+    socket.on('data', () => {});
     socket.end();
     socket.on('end', cb);
   });