apply style ci fix

Author: SjorsO

src/Filesystem.php

@@ -29,7 +29,7 @@ public function has(string $filename): bool
 
     /**
      * Get all file names in this directory that have the same name
-     * as $fileName, but have a different file extension
+     * as $fileName, but have a different file extension.
      * @param string $fileName
      * @return array
      */