[FEAT]: add new resource for private registries

### Describe the need

With [announcement of OIDC support](https://github.blog/changelog/2026-04-14-oidc-support-for-dependabot-and-code-scanning/) for Dependabot and CodeQL for private registries it will be nice to add new resource `github_private_registry`

[Main API](https://docs.github.com/en/rest/private-registries?apiVersion=2026-03-10) will be available in GoSDK in next release https://github.com/google/go-github/blob/master/github/private_registries.go just missing OIDC support https://github.com/google/go-github/issues/4158

### SDK Version

_No response_

### API Version

2026-03-10

### Relevant log output

```shell

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### Code of Conduct

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