feat(team_membership): allow id lookup from slug

[jhoenzsch]

Resolves #1501

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Behavior

Before the change?

• github_team_membership allows passing in the team slug as a team id.

After the change?

• github_team_membership allows passing in the team slug as a team id.

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Additional info

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)
• Added the appropriate label for the given change

Does this introduce a breaking change?

Please see our docs on breaking changes to help!

• Yes (Please add the Type: Breaking change label)
• No

If Yes, what's the impact:

• N/A

Pull request type

Please add the corresponding label for change this PR introduces:

• Bugfix: Type: Bug
• Feature/model/API additions: Type: Feature
• Updates to docs or samples: Type: Documentation
• Dependencies/code cleanup: Type: Maintenance

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[csainty]

This turned a parseInt() in to an api call - https://github.com/integrations/terraform-provider-github/blob/main/github/util.go#L163
We don't use this resource any longer, so I don't have a ready test setup, but unless there is caching down the stack this would have been an explosion of requests (X users * Y repos).

[dennislapchenko]

@jhoenzsch Hey. You think same can be done for github_team_members resource?
edit: did it myself 😁

[kfcampbell]

@csainty are you experiencing this effect yourself yet?

[csainty]

@kfcampbell No we don't use it, I was just browsing the release notes and reading diffs.