Rename properties

Rename `webwolf.url.*` to `webwolf.*.url` making it easier to move to a configuration class as no nested property is necessary

webgoat-lessons/challenge/src/main/java/org/owasp/webgoat/challenges/challenge7/Assignment7.java

@@ -46,7 +46,7 @@ public class Assignment7 extends AssignmentEndpoint {
 
     @Autowired
     private RestTemplate restTemplate;
-    @Value("${webwolf.url.mail}")
+    @Value("${webwolf.mail.url}")
     private String webWolfMailURL;
 
     @GetMapping("/challenge/7/reset-password/{link}")