Merge branch '5.0'

* 5.0:
  Tweak the code to avoid fabbot false positives
  Remove UPGRADE files for 4.x

Author: fabpot

Security/User/EntityUserProvider.php

@@ -92,7 +92,7 @@ public function refreshUser(UserInterface $user)
 
             $refreshedUser = $repository->find($id);
             if (null === $refreshedUser) {
-                throw new UsernameNotFoundException(sprintf('User with id %s not found.', json_encode($id)));
+                throw new UsernameNotFoundException('User with id '.json_encode($id).' not found.'));
             }
         }