bug #887 JWTAuthenticator logic fix (ergnuor)

This PR was merged into the 2.x branch.

Discussion
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JWTAuthenticator logic fix

Am I right or just missing something? :)

Commits
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0664d2a JWTAuthenticator logic fix

Security/Authenticator/JWTAuthenticator.php

@@ -189,7 +189,7 @@ protected function loadUser(array $payload, string $identity): UserInterface
                 }
             }
 
-            if(!class_exists(UsernameNotFoundException::class)) {
+            if(!class_exists(UserNotFoundException::class)) {
                 $ex = new UsernameNotFoundException(sprintf('There is no user with username "%s".', $identity));
                 $ex->setUsername($identity);
             } else {