[FEAT]: Unarchive if repository already exists

[arunsathiya]

Describe the need

This is not a feature request just yet, but needs to be a discussion on what the behavior should be when we try to create a repository that already exists, in an archived state.

Current behavior for unarchived-but-existing repositories

The current behavior for unarchived-but-existing repositories is, we get a successful state update that the infrastructure matches configuration:

terraform {
  required_providers {
    github = {
      source  = "integrations/github"
      version = "~> 5.0"
    }
  }
}

provider "github" {}

resource "github_repository" "example" {
  name               = "example"
  description        = "My awesome codebase"
  visibility         = "public"
  archive_on_destroy = false
}

Output:

╷
│ Warning: Provider development overrides are in effect
│
│ The following provider development overrides are set in the CLI configuration:
│  - integrations/github in /Users/arun/go/bin
│
│ 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.
╵
github_repository.example: Refreshing state... [id=archive]

No changes. Your infrastructure matches the configuration.

Terraform has compared your real infrastructure against your configuration and found no differences, so no changes are needed.

Current behavior for archived-but-existing repositories

If the repository is archived, trying to recreate it fails:

terraform {
  required_providers {
    github = {
      source  = "integrations/github"
      version = "~> 5.0"
    }
  }
}

provider "github" {}

resource "github_repository" "example" {
  name               = "archive"
  description        = "My awesome codebase"
  visibility         = "public"
  archive_on_destroy = true
}

Upon deletion, which results in archiving:

╷
│ Warning: Provider development overrides are in effect
│
│ The following provider development overrides are set in the CLI configuration:
│  - integrations/github in /Users/arun/go/bin
│
│ 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.
╵
github_repository.example: Destroying... [id=archive]
github_repository.example: Destruction complete after 1s

Apply complete! Resources: 0 added, 0 changed, 1 destroyed.

Upon recreation:

╷
│ Warning: Provider development overrides are in effect
│
│ The following provider development overrides are set in the CLI configuration:
│  - integrations/github in /Users/arun/go/bin
│
│ 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.
╵

Terraform used the selected providers to generate the following execution plan. Resource actions are indicated with the following symbols:
  + create

Terraform will perform the following actions:

  # github_repository.example will be created
  + resource "github_repository" "example" {
      + allow_auto_merge            = false
      + allow_merge_commit          = true
      + allow_rebase_merge          = true
      + allow_squash_merge          = true
      + archive_on_destroy          = true
      + archived                    = false
      + default_branch              = (known after apply)
      + delete_branch_on_merge      = false
      + description                 = "My awesome codebase"
      + etag                        = (known after apply)
      + full_name                   = (known after apply)
      + git_clone_url               = (known after apply)
      + html_url                    = (known after apply)
      + http_clone_url              = (known after apply)
      + id                          = (known after apply)
      + merge_commit_message        = "PR_TITLE"
      + merge_commit_title          = "MERGE_MESSAGE"
      + name                        = "archive"
      + node_id                     = (known after apply)
      + primary_language            = (known after apply)
      + private                     = (known after apply)
      + repo_id                     = (known after apply)
      + squash_merge_commit_message = "COMMIT_MESSAGES"
      + squash_merge_commit_title   = "COMMIT_OR_PR_TITLE"
      + ssh_clone_url               = (known after apply)
      + svn_url                     = (known after apply)
      + topics                      = (known after apply)
      + visibility                  = "public"
      + web_commit_signoff_required = false
    }

Plan: 1 to add, 0 to change, 0 to destroy.

─────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────

Saved the plan to: plan.tfplan

To perform exactly these actions, run the following command to apply:
    terraform apply "plan.tfplan"

### SDK Version

_No response_

### API Version

_No response_

### Relevant log output

_No response_

### Code of Conduct

- [X] I agree to follow this project's Code of Conduct

[kfcampbell]

what the behavior should be when we try to create a repository that already exists, in an archived state.

Hmm...I'd probably try to match the API's behavior in this case. I think that means throwing some form of error.