Update Stratigility, use http-interop middleware

src/Http/Middleware/AuthenticateWithHeader.php

@@ -14,18 +14,15 @@ namespace Flarum\Http\Middleware;
 use Flarum\Api\ApiKey;
 use Flarum\Http\AccessToken;
 use Flarum\User\User;
-use Psr\Http\Message\ResponseInterface as Response;
+use Interop\Http\ServerMiddleware\DelegateInterface;
+use Interop\Http\ServerMiddleware\MiddlewareInterface;
 use Psr\Http\Message\ServerRequestInterface as Request;
-use Zend\Stratigility\MiddlewareInterface;
 
 class AuthenticateWithHeader implements MiddlewareInterface
 {
     const TOKEN_PREFIX = 'Token ';
 
-    /**
-     * {@inheritdoc}
-     */
-    public function __invoke(Request $request, Response $response, callable $out = null)
+    public function process(Request $request, DelegateInterface $delegate)
     {
         $headerLine = $request->getHeaderLine('authorization');
 
@@ -53,7 +50,7 @@ class AuthenticateWithHeader implements MiddlewareInterface
             }
         }
 
-        return $out ? $out($request, $response) : $response;
+        return $delegate->process($request);
     }
 
     private function getUser($string)