Update ImportController.php

Author: 0x15f

src/Http/Controllers/ImportController.php

@@ -38,7 +38,7 @@ public function preview(NovaRequest $request, $file)
         $resources = collect(Nova::$resources);
 
         $resources = $resources->filter(function ($resource) {
-            return isset($resource::$canImportResource) && $resource::$canImportResource;
+            return property_exists((string) $resource, 'canImportResource') && $resource::$canImportResource;
         });
 
         $fields = $resources->map(function ($resource) {