(#7237) Add explicit `--force` flag.
(#7237) Add explicit `--force` flag.

This change also means that `puppet node terminate` will avoid accidentally
destroying more than one instance by default.

Reviewed-By: Max Martin
amos6224/puppetlabs-cloud-provisioner,puppetlabs/puppetlabs-cloud_provisioner,puppetlabs/puppetlabs-cloud_provisioner,16nsk/puppetlabs-cloud_provisioner