`@contentlayer2/utils` depends on deprecated `memfs@3.6.0`

[Here](https://github.com/timlrx/contentlayer2/blob/4847872f592dd16057565121af65217e70570c80/packages/%40contentlayer/utils/package.json#L75C6-L75C22)

[memfs@3.6.0](https://www.npmjs.com/package/memfs/v/3.6.0) has been re-released as memfs v4.