fixed ConfidentialClientApplication

application/confidentialClient/src/main/java/org/fuseri/confidentialclient/ConfidentialClientApplication.java

@@ -61,7 +61,7 @@ public class ConfidentialClientApplication {
                         try {
                             userRegisterRestTemplate.postForObject(url, createDto, UserCreateDto.class);
                         } catch (RestClientException e) {
-                            throw new ServletException("Unable to register user" + System.getenv("DOCKER_RUNNING"), e);
+                            throw new ServletException("Unable to register user", e);
                         }
                     }
                     super.onAuthenticationSuccess(req, res, auth);