@types/fs-extra needs to be updated to account for changes in Node v10.10+.
Tagging @alan-agius4 @midknight41 @shiftkey @mees- @jrockwood

Relevant bits of the changelog are:

2018-10-10, Version 10.12.0

Notable changes

• fs
  • Added a recursive option to fs.mkdir and fs.mkdirSync. If this option
    is set to true, non-existing parent folders will be automatically created. #21875

2018-09-06, Version 10.10.0

Notable Changes

• fs:
  • The methods fs.read, fs.readSync, fs.write, fs.writeSync,
    fs.writeFile and fs.writeFileSync now all accept TypedArray and
    DataView objects. #22150
  • A new boolean option, withFileTypes, can be passed to fs.readdir and
    fs.readdirSync. If set to true, the methods return an array of directory
    entries. These are objects that can be used to determine the type of each
    entry and filter them based on that without calling fs.stat. #22020