Fix some return types in tests

Author: nicolas-grekas

src/Symfony/Bundle/SecurityBundle/Tests/DataCollector/SecurityDataCollectorTest.php

@@ -434,7 +434,7 @@ private function getRoleHierarchy()
 
 final class DummyVoter implements VoterInterface
 {
-    public function vote(TokenInterface $token, $subject, array $attributes)
+    public function vote(TokenInterface $token, $subject, array $attributes): int
     {
     }
 }

src/Symfony/Component/HttpKernel/Tests/EventListener/DumpListenerTest.php

@@ -74,7 +74,7 @@ public function cloneVar($var): Data
 
 class MockDumper implements DataDumperInterface
 {
-    public function dump(Data $data)
+    public function dump(Data $data): ?string
     {
         echo '+'.$data->getValue();
     }

src/Symfony/Component/Security/Http/Tests/Authenticator/AbstractLoginFormAuthenticatorTest.php

@@ -11,6 +11,7 @@
 
 namespace Symfony\Component\Security\Http\Tests\Authenticator;
 
+use Symfony\Component\Security\Http\Authenticator\Passport\Passport;
 use PHPUnit\Framework\TestCase;
 use Symfony\Component\HttpFoundation\Request;
 use Symfony\Component\HttpFoundation\Response;
@@ -109,7 +110,7 @@ protected function getLoginUrl(Request $request): string
         return $this->loginUrl;
     }
 
-    public function authenticate(Request $request)
+    public function authenticate(Request $request): Passport
     {
         return new SelfValidatingPassport(new UserBadge('dummy'));
     }

src/Symfony/Component/Security/Http/Tests/EventListener/PasswordMigratingListenerTest.php

@@ -173,15 +173,15 @@ public function loadUserByIdentifier(string $identifier): UserInterface
     {
     }
 
-    public function refreshUser(UserInterface $user)
+    public function refreshUser(UserInterface $user): UserInterface
     {
     }
 
-    public function supportsClass(string $class)
+    public function supportsClass(string $class): bool
     {
     }
 
-    public function loadUserByUsername(string $username)
+    public function loadUserByUsername(string $username): UserInterface
     {
     }
 }
@@ -214,7 +214,7 @@ public function eraseCredentials()
     {
     }
 
-    public function getUsername()
+    public function getUsername(): string
     {
     }