Expected behavior

Should be able to remove a directory and then add a new directory that overlaps with the removed one.

Actual behavior

Docker for Mac refuses to do this, complaining there's an overlap.

Steps to reproduce the behavior

1. Under File Sharing tab, add /Users/foo (which overlaps with /Users, obviously).
2. Save and restart. App will refuse.
3. Remove /Users.
4. Save and restart. App will still refuse, even though there's no overlap anymore.