display a warning instead of an error if the project_id is a duplicate

CRM/Twingle/Profile.php

@@ -296,7 +296,7 @@ class CRM_Twingle_Profile {
               2 => $profile->getName()
             ]
           ),
-          ProfileValidationError::ERROR_CODE_PROFILE_VALIDATION_FAILED
+          ProfileValidationError::ERROR_CODE_PROFILE_VALIDATION_WARNING
         );
       }
     }