Add missing output fields to Certificate resource.

[modular-magician]

Updated a couple of mistakes in fields descriptions. Changed type of
Certificate.Managed.State from String to Enum.

If this PR is for Terraform, I acknowledge that I have:

• Searched through the issue tracker for an open issue that this either resolves or contributes to, commented on it to claim it, and written "fixes {url}" or "part of {url}" in this PR description. If there were no relevant open issues, I opened one and commented that I would like to work on it (not necessary for very small changes).
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• Ensured that all new fields I added that can be set by a user appear in at least one example (for generated resources) or third_party test (for handwritten resources or update tests).
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Release Note Template for Downstream PRs (will be copied)

certificatemanager: added `state`, `authorization_attempt_info` and `provisioning_issue` output fields to `google_certificate_manager_certificate`

Derived from GoogleCloudPlatform/magic-modules#6322