fix(manifest): do not output links with empty contents

Author: codepuncher

src/AcornFavicons.php

@@ -214,6 +214,7 @@ protected function generateWindowsMetaTags(): array
                 'content' => $this->getPublicPath('browserconfig.xml'),
             ],
         ];
+        $attributes = array_filter($attributes, fn (array $att): bool => ! empty($att['content']));
 
         return array_merge(
             $tags,