[esh-authz2] FormCredentialsExtractor - wrong configuration property

[svilenvul]

I have noticed that FormCredentialsExtractor is not configured as expected. A quick diff for reference :

     @Modified
     void update(Map<String, Object> properties) {
-        Object loginUri = properties.get(LOGIN_ENDPOINT);
+        Object loginUri = properties.get("loginEndpoint");
         if (loginUri != null && loginUri instanceof String) {
             this.loginEndpoint = (String) loginUri;
         }