Change time format to 24 hr

src/main/java/ChatClient.java

@@ -97,7 +97,7 @@ public class ChatClient extends JFrame implements KeyListener {
     }
 
     private void updateTime() {
-        SimpleDateFormat sdf = new SimpleDateFormat("hh:mm:ss a");
+        SimpleDateFormat sdf = new SimpleDateFormat("HH:mm:ss");
         String currentTime = sdf.format(new Date());
         timeLabel.setText("Current Time: " + currentTime);
     }