Fix bare-metal multiple apply/ssh on Terraform v0.11.4+

[dghubble]

• Terraform v0.11.4 introduced changes to remote-exec that mean Typhoon bare-metal clusters require multiple runs of terraform apply to ssh and bootstrap.
• Bare-metal installs PXE boot a live instance to install to disk and then reboot from disk as controllers/workers.Terraform remote-exec has no way to "know" to wait until the reboot has occurred to kickoff Kubernetes bootstrap. Previously Typhoon created a "debug" user during this install phase to allow an admin to SSH, but remote-exec would hang, trying to connect as user "core". Terraform v0.11.4 changes this behavior so remote-exec fails and a user must re-run terraform apply until succeeding.
• A new way to "trick" remote-exec into waiting for the reboot into the disk install is to run SSH on a non-standard port during the disk install. This retains the ability for an admin to SSH during install (most distros don't have this) and fixes the issue so only a single run of terraform apply is needed.
• Halt on provisioner errors hashicorp/terraform#17359 (comment)