Mercurial 6.4 was recently released and showing up in package managers. With
the update to 6.4 using `arc land` would result in an exception indicating that
`expandpath` function does not exist.
The `ui.expandpath` function was deprecated in 5.8 and now removed in 6.4. The
functionality has been moved to `utils.urlutil.get_` functions (they are split
between getting pull, push, and clone paths).
This updates the script to try `utils.urlutil.get_clone_path` function if the
`ui.expandpath` function is not present.