feat: Add data source to retrieve repo environment public key

[tiberium]

Resolves: Lack of a data source delivering a Public Key of a Repo's Environment

---

Before the change?

Not possible to retrieve the Public Key of a Environment in a Repository.

After the change?

Brand new data source delivering a Public Key created automatically by GitHub when a new Environment is created in a Repository.

• Retrieving the organization public key, repository public key, user public key, dependabot public key and codespaces public key are already implemented. This PR brings the lacking Environment Public Key.

Pull request checklist

• Tests for the changes have been added (for bug fixes / features)
• Docs have been reviewed and added / updated if needed (for bug fixes / features)

Does this introduce a breaking change?

No breaking changes introduced.

Please see our docs on breaking changes to help!

• Yes
• No

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[kfcampbell]

In addition to the trivially fixed failing check, I'm getting an error when running the introduced integration test:

  | Error running apply: exit status 1
  | 
  | Error: Incorrect attribute value type
  | 
  |   on terraform_plugin_test.tf line 14, in data "github_actions_environment_public_key" "test":
  |   14: \t\t\t\trepository_id\t= github_repository.test.id
  |     ├────────────────
  |     │ github_repository.test.id is "tf-acc-test-36mpg"
  | 
  | Inappropriate value for attribute "repository_id": a number is required.

Can you reproduce that?

[tiberium]

Hi @kfcampbell ,
sorry for the failing test, should work now. I added 2 new commits: one for the typo in docs, second one addressing the failing test. Should I squash everything into one commit and force-push here?