bug #3477 Api key user provider should use "implements" instead of "extends" (skowi)

This PR was merged into the 2.4 branch.

Discussion
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Api key user provider should use "implements" instead of "extends"

Commits
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f1c1273 ApiKeyUserProvider should implements UserProviderInterface
f39686a Changed extends to implements

Author: weaverryan

cookbook/security/api_key_authentication.rst

@@ -145,7 +145,7 @@ The ``$userProvider`` might look something like this::
     use Symfony\Component\Security\Core\User\UserInterface;
     use Symfony\Component\Security\Core\Exception\UnsupportedUserException;
 
-    class ApiKeyUserProvider extends UserProviderInterface
+    class ApiKeyUserProvider implements UserProviderInterface
     {
         public function getUsernameForApiKey($apiKey)
         {
@@ -414,7 +414,7 @@ of the user to make sure it's not out-of-date. But regardless of your requiremen
     // src/Acme/HelloBundle/Security/ApiKeyUserProvider.php
 
     // ...
-    class ApiKeyUserProvider extends UserProviderInterface
+    class ApiKeyUserProvider implements UserProviderInterface
     {
         // ...