fix(symfony): allow route default _format configuration

Author: soyuka

src/Symfony/Routing/ApiLoader.php

@@ -90,11 +90,10 @@ public function load(mixed $data, ?string $type = null): RouteCollection
                         $path,
                         [
                             '_controller' => $controller ?? 'api_platform.action.placeholder',
-                            '_format' => null,
                             '_stateless' => $operation->getStateless(),
                             '_api_resource_class' => $resourceClass,
                             '_api_operation_name' => $operationName,
-                        ] + ($operation->getDefaults() ?? []),
+                        ] + ($operation->getDefaults() ?? []) + ['_format' => null],
                         $operation->getRequirements() ?? [],
                         $operation->getOptions() ?? [],
                         $operation->getHost() ?? '',

tests/Symfony/Routing/ApiLoaderTest.php

@@ -321,7 +321,7 @@ private function getRoute(string $path, string $controller, ?bool $stateless, st
             $path,
             [
                 '_controller' => $controller,
-                '_format' => null,
+                '_format' => $extraDefaults['_format'] ?? null,
                 '_stateless' => $stateless,
                 '_api_resource_class' => $resourceClass,
                 '_api_operation_name' => $operationName,