Switch to S3 terraform backend

[Alex-Welsh]

This change is a work in progress. Please do not merge it before it's ready. We could end up with a horrible mess if we have competing state files. This should all work now

Recent changes to the free tier of terraform cloud mean we can't use it anymore. Switching to an S3-compatible object store instead.

TODO:

• Ensure locking works Locking works!
• Ensure old statefile is removed so we atomically switch statefile in terraform cloud has been locked
• Apply same change to other repos (e.g. terraform-bastion)
• Switch to tofu

[gemini-code-assist]

Code Review

This pull request updates the GitHub provider to version 6.11.1 and migrates the Terraform state backend from Terraform Cloud to a Cloudflare R2 S3-compatible storage. Review feedback suggests correcting the indentation of the backend configuration and adding a required_version constraint to ensure compatibility with the use_lockfile feature, which is only available in recent versions of Terraform and OpenTofu.

[stackhpc-ci]

Terraform Format and Style 🖌success

Terraform Initialization ⚙️success

Terraform Validation 🤖success

Validation Output

Warning: Deprecated attribute

  on repositories.tf line 20, in resource "github_repository" "repositories":
  20:       has_downloads,

The attribute "has_downloads" is deprecated. Refer to the provider
documentation for details.
Success! The configuration is valid, but there were some validation warnings
as shown above.

Terraform Plan 📖success

Show Plan

undefined

Pusher: @Alex-Welsh, Action: pull_request, Working Directory: ``, Workflow: Terraform GitHub