I am using vfsStream to mock the file system as a service during the execution of a Symony app. `file_put_content()` fails when creating another root dir was created. Is there a way to have 2 root dirs, is it a bug or by design? Steps to reproduce: ```php $root = vfsStream::setup('root'); mkdir($dir = $root->url() . '/test/code-65b3c45ed2883/64/1b/4e', 0777, true); file_put_contents($dir . '/Works.txt', 'content'); $other = vfsStream::setup('other'); mkdir($dir = $root->url() . '/test/code-65b3c45ed2883/42/ff/91', 0777, true); file_put_contents($dir . '/Fails.txt', 'content'); "PHP Warning: file_put_contents(vfs://root/test/code-65b3c45ed2883/42/ff/91/Fails.txt): failed to open stream: "org\bovigo\vfs\vfsStreamWrapper::stream_open" call failed in ..." ``` Thank you for this great project.