Add validation to `default_labels`

[zachberger]

Community Note

• Please vote on this issue by adding a 👍 reaction to the original issue to help the community and maintainers prioritize this request.
• Please do not leave +1 or me too comments, they generate extra noise for issue followers and do not help prioritize the request.
• If you are interested in working on this issue or have submitted a pull request, please leave a comment.
• If an issue is assigned to a user, that user is claiming responsibility for the issue.
• Customers working with a Google Technical Account Manager or Customer Engineer can ask them to reach out internally to expedite investigation and resolution of this issue.

Description

Label values must conform to the regexp [\p{Ll}\p{Lo}\p{N}_-]{0,63}. It would be good to add validation to default_labels argument so that plans fail if an invalid label value is passed instead of waiting for the API to reject it during apply.

New or Affected Resource(s)

The provider

Potential Terraform Configuration

References

https://cloud.google.com/compute/docs/labeling-resources#requirements

[rileykarson]

Note from triage: This is probably reasonable since we're applying the values directly. I'm not sure if there are labels fields with different validation rules anywhere- but we'd probably want to exclude them from default_labels if so.