let os assign ephemeral port

Author: Skn0tt

playwright/src/test/java/com/microsoft/playwright/Utils.java

@@ -37,24 +37,12 @@
 import static org.junit.jupiter.api.Assertions.assertEquals;
 
 public class Utils {
-  private static final AtomicInteger nextUnusedPort = new AtomicInteger(9000);
-
-  private static boolean available(int port) {
-    try (ServerSocket ignored = new ServerSocket(port)) {
-      return true;
-    } catch (IOException ignored) {
-      return false;
-    }
-  }
-
   public static int nextFreePort() {
-    for (int i = 0; i < 100; i++) {
-      int port = nextUnusedPort.getAndIncrement();
-      if (available(port)) {
-        return port;
-      }
+    try (ServerSocket socket = new ServerSocket(0)) {
+      return socket.getLocalPort();
+    } catch (IOException e) {
+      throw new RuntimeException("Cannot find free port", e);
     }
-    throw new RuntimeException("Cannot find free port: " + nextUnusedPort.get());
   }
 
   static void assertJsonEquals(Object expected, Object actual) {