fix basepath in redirecthandler

Author: LordSimal

src/Middleware/UnauthorizedHandler/CakeRedirectHandler.php

@@ -77,6 +77,11 @@ protected function getUrl(ServerRequestInterface $request, array $options): stri
             $url['?'][$options['queryParam']] = $redirect;
         }
 
+        $requestBase = $request->getAttribute('base');
+        if ($requestBase) {
+            $url['_base'] = $requestBase;
+        }
+
         return Router::url($url);
     }
 }

tests/TestCase/Middleware/UnauthorizedHandler/CakeRedirectHandlerTest.php

@@ -129,10 +129,10 @@ public function testHandleRedirectWithBasePath()
         $handler = new CakeRedirectHandler();
         $exception = new Exception();
 
-        Configure::write('App.base', '/basedir');
         $request = ServerRequestFactory::fromGlobals(
             ['REQUEST_URI' => '/admin/dashboard']
         );
+        $request = $request->withAttribute('base', '/basedir');
 
         $response = $handler->handle($exception, $request, [
             'exceptions' => [