[FEAT]: support write-only secrets attributes for webhook resources

[tdyas]

Describe the need

The webhook resources (github_repository_webhook and github_organization_webhook) have a secret attribute which is not write-only, and thus the secret is persisted in Terraform state.

A better pattern used in other Terraform providers is to support write-only attributes secret_wo and secret_wo_version so that the secrets can be sourced from ephemeral resources and not persisted to the Terraform state nor included in a plan.

GitHub Installation Type

• GitHub.com (Free, Pro, or Team)
• GitHub Enterprise Server (on-premises)
• GitHub Enterprise Cloud with Personal Accounts (github.com)
• GitHub Enterprise Cloud with Managed Users/EMU (github.com)
• GitHub Enterprise Cloud with Data Residency (*.ghe.com)
• I don't know

Relevant log output

Code of Conduct

• I agree to follow this project's Code of Conduct

[github-actions]

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[stevehipwell]

Thanks for the issue report @tdyas. We're aware of the potential for supporting write only attributes and will be evaluating a pattern for this to be applied across the provider.

[tdyas]

I made a PR related to just the webhook resources. It uses the _wo and _wo_version convention that I've seen in other providers.

That convention though may not be good for the resources for GitHub Actions secrets since there are attributes for plain text and encrypted values. Adding _wo and _wo_version attribute variants on those resources may be too complex of a user experience.

[stevehipwell]

@tdyas thanks for the issue but as a rule of thumb you're best off waiting for an issue to be triaged before opening a PR as this project has limited maintainer resources.

Before adding new functionality to existing resources they need to be updated to the latest pattern (see RESOURCES.md). And when adding a new pattern to the provider (write only is a new pattern) we need to make sure that the implementation pattern is architected correctly.