The unminimize script will try to install the lxd snap using the shim script
`/usr/sbin/lxd` from the lxd-installer package.
Previously `unminimize` was using `snap`
to install `lxd` directly which was being diverted by diverting the `snap` command.
This is no longer the case so we can remove `/usr/sbin/lxd` from the lxd-installer package
if it exists and then redirect any calls to `/usr/sbin/lxd` to `/bin/true`.
