Whois improvement

app/src/main/java/eu/faircode/email/Whois.java

@@ -25,6 +25,7 @@ import java.net.Socket;
 import java.net.UnknownHostException;
 
 public class Whois {
+    // https://datatracker.ietf.org/doc/html/rfc812
     private static final int WHOIS_PORT = 43;
     private static final int WHOIS_TIMEOUT = 15 * 1000; // milliseconds
 
@@ -40,7 +41,7 @@ public class Whois {
         Socket socket = new Socket();
         socket.connect(new InetSocketAddress(host, port), WHOIS_TIMEOUT);
         try {
-            socket.getOutputStream().write((domain + "\n").getBytes());
+            socket.getOutputStream().write((domain + "\r\n").getBytes());
             return host + ":" + port + "\n" + Helper.readStream(socket.getInputStream());
         } finally {
             socket.close();