feat: add new tool versions datasource

[Apollorion]

Description of the change

Introduce new tool versions datasource, will list out supported tool versions for KUBECTL, OPEN_TOFU, TERRAFORM_FOSS, and TERRAGRUNT.

data "spacelift_tool_versions" "test" {
    tool = "TERRAFORM_FOSS"
}

Type of change

• Bug fix (non-breaking change that fixes an issue)
• New feature (non-breaking change that adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation (non-breaking change that adds documentation)

Checklists

Development

• Lint rules pass locally
• The code changed/added as part of this pull request has been covered with tests
• All tests related to the changed code pass in development
• Examples for new resources and data sources have been added
• Default values have been documented in the description (e.g., "Dummy: (Boolean) Blah blah. Defaults to false.)
• If the action fails that checks the documentation: Run go generate to make sure the docs are up to date

Code review

• This pull request has a descriptive title and information useful to a reviewer. There may be a screenshot or screencast attached
• Pull Request is no longer marked as "draft"
• Reviewers have been assigned
• Changes have been reviewed by at least one other engineer

[Apollorion]

Im not entirely sure why the test is failing, are these queries gated in some fashion that I cannot see? I cant imagine it, all these queries work even anonymously.

I thought this might have been a difference in the way the provider is authenticated to spacelift in CI vs my local, but the tests pass locally no matter how I authenticate (generated token vs api key and id).

Built the plugin and ran it with tofu:

$ tofu apply
╷
│ Warning: Provider development overrides are in effect
│
│ The following provider development overrides are set in the CLI configuration:
│  - spacelift.io/spacelift-io/spacelift in /Users/apollorion/projects/src/github.com/spacelift-io/terraform-provider-spacelift/dist/terraform-provider-spacelift_darwin_arm64
│
│ The behavior may therefore not match any released version of the provider and applying changes may cause the state to become incompatible with published releases.
╵
data.spacelift_tool_versions.kubectl: Reading...
data.spacelift_tool_versions.terragrunt: Reading...
data.spacelift_tool_versions.terraform: Reading...
data.spacelift_tool_versions.opentofu: Reading...
data.spacelift_tool_versions.terragrunt: Read complete after 0s [id=spacelift-versions]
data.spacelift_tool_versions.opentofu: Read complete after 1s [id=spacelift-versions]
data.spacelift_tool_versions.kubectl: Read complete after 1s [id=spacelift-versions]
data.spacelift_tool_versions.terraform: Read complete after 1s [id=spacelift-versions]

Changes to Outputs:
  + kubectl    = {
      + id       = "spacelift-versions"
      + tool     = "KUBECTL"
      + versions = [
          + "1.31.1",
          + "1.31.0",
          + "1.30.5",
          ...(edited for brevity)
        ]
    }
  + terraform  = {
      + id       = "spacelift-versions"
      + tool     = "TERRAFORM_FOSS"
      + versions = [
          + "1.5.7",
          + "1.5.6",
          + "1.5.5",
          ...(edited for brevity)
        ]
    }
  + terragrunt = {
      + id       = "spacelift-versions"
      + tool     = "TERRAGRUNT"
      + versions = [
          + "0.67.2",
          + "0.67.1",
          + "0.67.0",
          ...(edited for brevity)
        ]
    }
  + tofu       = {
      + id       = "spacelift-versions"
      + tool     = "OPEN_TOFU"
      + versions = [
          + "1.8.4",
          + "1.8.3",
          + "1.8.2",
          ...(edited for brevity)
        ]
    }

I can also run the tests with no problem locally:

$ go test ./... -run 'TestToolVersionsData'
?   	github.com/spacelift-io/terraform-provider-spacelift	[no test files]
?   	github.com/spacelift-io/terraform-provider-spacelift/spacelift/internal	[no test files]
?   	github.com/spacelift-io/terraform-provider-spacelift/spacelift/internal/structs	[no test files]
?   	github.com/spacelift-io/terraform-provider-spacelift/spacelift/internal/structs/search	[no test files]
?   	github.com/spacelift-io/terraform-provider-spacelift/spacelift/internal/structs/search/predicates	[no test files]
?   	github.com/spacelift-io/terraform-provider-spacelift/spacelift/internal/structs/vcs	[no test files]
?   	github.com/spacelift-io/terraform-provider-spacelift/spacelift/internal/testhelpers	[no test files]
?   	github.com/spacelift-io/terraform-provider-spacelift/spacelift/internal/validations	[no test files]
ok  	github.com/spacelift-io/terraform-provider-spacelift/spacelift	32.917s

The error says Error running pre-apply refresh, but Im able to also run tofu refresh with no problems:

$ tofu refresh
data.spacelift_tool_versions.kubectl: Reading...
data.spacelift_tool_versions.opentofu: Reading...
data.spacelift_tool_versions.terragrunt: Reading...
data.spacelift_tool_versions.terraform: Reading...
data.spacelift_tool_versions.kubectl: Read complete after 0s [id=spacelift-versions]
data.spacelift_tool_versions.terragrunt: Read complete after 0s [id=spacelift-versions]
data.spacelift_tool_versions.terraform: Read complete after 0s [id=spacelift-versions]
data.spacelift_tool_versions.opentofu: Read complete after 0s [id=spacelift-versions]
╷
│ Warning: Empty or non-existent state
│
│ There are currently no remote objects tracked in the state, so there is nothing to refresh.
╵

I dont see what the difference is between CI and my local.

[adamconnelly]

Left one question, but other than that LGTM!

[adamconnelly]

@Apollorion the reason the tests are failing in CI is because of a bug in the Spacelift backend code. Here's the relevant error in the logs:

The problem is that the API key you'll have generated for local testing isn't quite the same as a Spacelift run token, and the GitHub Actions tests use a token that simulates a Spacelift run. I'll fix the backend issue just now.

[adamconnelly]

Ok, looks good, but let's not merge this until we get the backend fix released and the tests pass.

[Apollorion]

Pushed up the ID change, once that backend fix is in place tests should pass 👍 @adamconnelly @peterdeme need reapproval :)