[Misc] fix port intermittent conflict

Summary: fix port intermittent conflict for com/alibaba/wisp/WispMonitorDataTest.java, set PORT = 0

Test Plan: CI pipeline

Reviewed-by: lei.yul, lvfei.lv

Issue: dragonwell-project/dragonwell11#475

jdk/test/com/alibaba/wisp/WispMonitorDataTest.java

@@ -98,11 +98,13 @@ public static void main(String[] args) throws Exception {
     }
 
     private static ServerSocket ss;
-    private static final int PORT = 23002;
+    private static int port = 0;
     private static final int BUFFER_SIZE = 1024;
 
     private static void startNetServer() throws IOException {
-        ss = new ServerSocket(PORT);
+        ss = new ServerSocket(port);
+	port = ss.getLocalPort();
+	System.out.println("port get from os = " + port);
         Thread t = new Thread(() -> {
             try {
                 while (true) {
@@ -122,7 +124,7 @@ private static void startNetServer() throws IOException {
 
     private static void doNetIO() {
         try {
-            Socket so = new Socket("localhost", PORT);
+            Socket so = new Socket("localhost", port);
             OutputStream os = so.getOutputStream();
             os.write(new byte[BUFFER_SIZE]);
             os.flush();