Remove stale cloud-init cruft

🗣 Description

This pull request adds code to remove some stale cloud-init cruft inherited from the Kali base AMI we are using. It also picks up the bugfix from cisagov/ansible-role-cobalt-strike#44.

💭 Motivation and context

The Kali base AMI we are using does not seem to have run this to clean up after itself. If we don't do it then userdata, for instance, will be ignored and not run when our AMI is started.

Resolves cisagov/cool-system-internal#45.

See also cisagov/ansible-role-cobalt-strike#43.

🧪 Testing

I built and deployed a new AMI to our staging COOL environment and verified that the userdata was being run; in particular, I verified that with these changes the EFS share is being mounted as expected. I also verified that the Cobalt Strike deployment could now be upgraded.

✅ Checklist

[x] This PR has an informative and human-readable title.
[x] Changes are limited to a single goal - eschew scope creep!
[ ] All future TODOs are captured in issues, which are referenced in code comments.
[x] All relevant type-of-change labels have been added.
[x] I have read the CONTRIBUTING document.
[x] These code changes follow cisagov code standards.
[x] All new and existing tests pass.
[ ] Finalize version.

cisagov / kali-packer