resource/cloudflare_access_service_token: allow in place refreshing

[jacobbednarz]

Access Service Tokens are now refreshable and can be expiry extended in
place instead of recreation.

Closes #1866

[github-actions]

changelog detected ✅

[gitguardian]

⚠️ GitGuardian has uncovered 6 secrets following the scan of your pull request.

Please consider investigating the findings and remediating the incidents. Failure to do so may lead to compromising the associated services or software components.

🔎 Detected hardcoded secrets in your pull request

GitGuardian id	Secret	Commit	Filename
4318592	Generic High Entropy Secret	3c07bfb	examples/resources/cloudflare_pages_project/resource.tf	View secret
4318592	Generic High Entropy Secret	3c07bfb	internal/provider/resource_cloudflare_pages_project_test.go	View secret
4318592	Generic High Entropy Secret	3c07bfb	internal/provider/resource_cloudflare_pages_project_test.go	View secret
4318592	Generic High Entropy Secret	e2f675a	examples/resources/cloudflare_pages_project/resource.tf	View secret
4318592	Generic High Entropy Secret	e2f675a	internal/provider/resource_cloudflare_pages_project_test.go	View secret
4318592	Generic High Entropy Secret	e2f675a	internal/provider/resource_cloudflare_pages_project_test.go	View secret

🛠 Guidelines to remediate hardcoded secrets

1. Understand the implications of revoking this secret by investigating where it is used in your code.
2. Replace and store your secrets safely. Learn here the best practices.
3. Revoke and rotate these secrets.
4. If possible, rewrite git history. Rewriting git history is not a trivial act. You might completely break other contributing developers' workflow and you risk accidentally deleting legitimate data.

To avoid such incidents in the future consider

• following these best practices for managing and storing secrets including API keys and other credentials
• install secret detection on pre-commit to catch secret before it leaves your machine and ease remediation.

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<sup>🦉 GitGuardian detects secrets in your source code to help developers and security teams secure the modern development process. You are seeing this because you or someone else with access to this repository has authorized GitGuardian to scan your pull request.

Our GitHub checks need improvements? Share your feedbacks!</sup>

[github-actions]

This functionality has been released in v3.23.0 of the Terraform Cloudflare Provider.

Please see the Terraform documentation on provider versioning or reach out if you need any assistance upgrading.

For further feature requests or bug reports with this functionality, please create a new GitHub issue following the template. Thank you!