Small updates to servlet container test setup. (#12318)

* Small updates to servlet container test setup.

- Upgraded to use cargo-maven3-plugin since cargo-maven2-plugin is now
EOL.
- Defined supported packagings as the current jetty-maven-plugin default
only covers war.
- Changed a test pojo to implement Serializable in order to prevent an
error in cargo-maven3-plugin stop-container phase.

1 files changed, 3 insertions, 1 deletions

diff --git a/test/servlet-containers/generic-ui/src/main/java/com/vaadin/tests/integration/ServletIntegrationUI.java b/test/servlet-containers/generic-ui/src/main/java/com/vaadin/tests/integration/ServletIntegrationUI.java
index 0d4010beaa..670d0ca8d5 100644
--- a/test/servlet-containers/generic-ui/src/main/java/com/vaadin/tests/integration/ServletIntegrationUI.java
+++ b/test/servlet-containers/generic-ui/src/main/java/com/vaadin/tests/integration/ServletIntegrationUI.java
@@ -1,5 +1,7 @@
 package com.vaadin.tests.integration;
 
+import java.io.Serializable;
+
 import com.vaadin.annotations.DesignRoot;
 import com.vaadin.annotations.Widgetset;
 import com.vaadin.server.ClassResource;
@@ -15,7 +17,7 @@ import com.vaadin.ui.declarative.Design;
 @Widgetset("com.vaadin.DefaultWidgetSet")
 public class ServletIntegrationUI extends UI {
 
-    public static class Country {
+    public static class Country implements Serializable {
         private final String name;
         private final String id;
         private final Resource icon;