JAVA-25341 fix Java networking flaky tests (#14798)

core-java-modules/core-java-networking/src/test/java/com/baeldung/socket/EchoIntegrationTest.java

@@ -24,7 +24,7 @@ public class EchoIntegrationTest {
 
         Executors.newSingleThreadExecutor()
             .submit(() -> new EchoServer().start(port));
-        Thread.sleep(500);
+        Thread.sleep(2000);
     }
 
     private EchoClient client = new EchoClient();

core-java-modules/core-java-networking/src/test/java/com/baeldung/socket/GreetServerIntegrationTest.java

@@ -27,7 +27,7 @@ public class GreetServerIntegrationTest {
         
         Executors.newSingleThreadExecutor()
             .submit(() -> new GreetServer().start(port));
-        Thread.sleep(500);
+        Thread.sleep(2000);
     }
 
     @Before

core-java-modules/core-java-networking/src/test/java/com/baeldung/socket/SocketEchoMultiIntegrationTest.java

@@ -23,7 +23,7 @@ public class SocketEchoMultiIntegrationTest {
         s.close();
 
         Executors.newSingleThreadExecutor().submit(() -> new EchoMultiServer().start(port));
-        Thread.sleep(500);
+        Thread.sleep(2000);
     }
 
     @Test