test: make testWebsocketClientClose more reliable for async environments

Signed-off-by: Marc Nuri <[email protected]>

httpclient-tests/src/test/java/io/fabric8/kubernetes/client/http/OkHttpClientTest.java

@@ -79,7 +79,7 @@ void testWebsocketClientClose() throws InterruptedException, ExecutionException,
     server.expect().withPath("/wsclose")
         .andUpgradeToWebSocket()
         .open()
-        .expect("never sent").andEmit("response").always().done().always();
+        .waitFor(100L).andEmit("response").done().always();
 
     CompletableFuture<String> closeReason = new CompletableFuture<>();