Add missing tests

Author: nikolaseu

src/test/java/com/auth0/json/mgmt/guardian/EnrollmentTicketTest.java

@@ -23,6 +23,25 @@ public void shouldSerializeDataToBeSent() throws Exception {
         assertThat(serialized, JsonMatcher.hasEntry("email", "me@auth0.com"));
     }
 
+    @Test
+    public void shouldSerializeDataToBeSentOnlyUserId() throws Exception {
+        EnrollmentTicket ticket = new EnrollmentTicket("1");
+
+        String serialized = toJSON(ticket);
+        assertThat(serialized, is(notNullValue()));
+        assertThat(serialized, JsonMatcher.hasEntry("user_id", "1"));
+    }
+
+    @Test
+    public void shouldSerializeDataToBeSentOnlyUserIdAndSendEmail() throws Exception {
+        EnrollmentTicket ticket = new EnrollmentTicket("1", true);
+
+        String serialized = toJSON(ticket);
+        assertThat(serialized, is(notNullValue()));
+        assertThat(serialized, JsonMatcher.hasEntry("user_id", "1"));
+        assertThat(serialized, JsonMatcher.hasEntry("send_mail", true));
+    }
+
     @Test
     public void shouldIncludeReadOnlyValuesOnDeserialize() throws Exception {
         EnrollmentTicket ticket = fromJSON(readOnlyJson, EnrollmentTicket.class);