Set SameSite policy for Cookie (#242)

Author: sake92

src/main/java/org/pac4j/undertow/context/UndertowWebContext.java

@@ -122,6 +122,7 @@ public void addResponseCookie(final Cookie cookie) {
         newCookie.setMaxAge(cookie.getMaxAge() < 0 ? null : cookie.getMaxAge());
         newCookie.setSecure(cookie.isSecure());
         newCookie.setHttpOnly(cookie.isHttpOnly());
+        newCookie.setSameSiteMode(cookie.getSameSitePolicy());
         getExchange().setResponseCookie(newCookie);
     }