Fix Psalm errors

Author: fabpot

src/Symfony/Bundle/SecurityBundle/Tests/Functional/Bundle/AccessTokenBundle/Security/Http/JsonAuthenticationSuccessHandler.php

@@ -19,7 +19,7 @@
 
 class JsonAuthenticationSuccessHandler implements AuthenticationSuccessHandlerInterface
 {
-    public function onAuthenticationSuccess(Request $request, TokenInterface $token): Response
+    public function onAuthenticationSuccess(Request $request, TokenInterface $token): ?Response
     {
         return new JsonResponse(['message' => sprintf('Good game @%s!', $token->getUserIdentifier())]);
     }

src/Symfony/Bundle/SecurityBundle/Tests/Functional/Bundle/JsonLoginBundle/Security/Http/JsonAuthenticationSuccessHandler.php

@@ -19,7 +19,7 @@
 
 class JsonAuthenticationSuccessHandler implements AuthenticationSuccessHandlerInterface
 {
-    public function onAuthenticationSuccess(Request $request, TokenInterface $token): Response
+    public function onAuthenticationSuccess(Request $request, TokenInterface $token): ?Response
     {
         return new JsonResponse(['message' => sprintf('Good game @%s!', $token->getUserIdentifier())]);
     }

src/Symfony/Bundle/SecurityBundle/Tests/Functional/Bundle/LoginLink/TestCustomLoginLinkSuccessHandler.php

@@ -19,7 +19,7 @@
 
 class TestCustomLoginLinkSuccessHandler implements AuthenticationSuccessHandlerInterface
 {
-    public function onAuthenticationSuccess(Request $request, TokenInterface $token): Response
+    public function onAuthenticationSuccess(Request $request, TokenInterface $token): ?Response
     {
         return new JsonResponse(['message' => sprintf('Welcome %s!', $token->getUserIdentifier())]);
     }

src/Symfony/Component/Security/Http/Authentication/CustomAuthenticationSuccessHandler.php

@@ -37,7 +37,7 @@ public function __construct(AuthenticationSuccessHandlerInterface $handler, arra
         }
     }
 
-    public function onAuthenticationSuccess(Request $request, TokenInterface $token): Response
+    public function onAuthenticationSuccess(Request $request, TokenInterface $token): ?Response
     {
         return $this->handler->onAuthenticationSuccess($request, $token);
     }

src/Symfony/Component/Security/Http/Authentication/DefaultAuthenticationSuccessHandler.php

@@ -52,7 +52,7 @@ public function __construct(HttpUtils $httpUtils, array $options = [], LoggerInt
         $this->setOptions($options);
     }
 
-    public function onAuthenticationSuccess(Request $request, TokenInterface $token): Response
+    public function onAuthenticationSuccess(Request $request, TokenInterface $token): ?Response
     {
         return $this->httpUtils->createRedirectResponse($request, $this->determineTargetUrl($request));
     }