WW-5190 Marks all Struts related filters with <async-supported/>

Author: lukaszlenart

apps/showcase/src/main/webapp/WEB-INF/web.xml

@@ -42,11 +42,13 @@
     <filter>
         <filter-name>struts-execute</filter-name>
         <filter-class>org.apache.struts2.dispatcher.filter.StrutsExecuteFilter</filter-class>
+        <async-supported>true</async-supported>
     </filter>
 
     <filter>
         <filter-name>sitemesh</filter-name>
         <filter-class>com.opensymphony.sitemesh.webapp.SiteMeshFilter</filter-class>
+        <async-supported>true</async-supported>
     </filter>
 
     <filter-mapping>

apps/showcase/src/test/java/it/org/apache/struts2/showcase/DispatcherResultTest.java

@@ -40,6 +40,7 @@ public void testDispatchingToJSP() throws Exception {
     @Test
     public void testDispatchingToAction() throws Exception {
         try (final WebClient webClient = new WebClient()) {
+            webClient.getOptions().setThrowExceptionOnFailingStatusCode(false);
             final HtmlPage page = webClient.getPage(ParameterUtils.getBaseUrl() + "/dispatcher/forward.action");
 
             //DomElement div = page.getElementById("dispatcher-result");