Supporting labelling of disks

[chrisst]

upstreaming / closes https://github.com/terraform-providers/terraform-provider-google/pull/3766/files

Release Note for Downstream PRs (will be copied)

Support labelling for compute_instance boot_disks and compute_instance_template disks.

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[modular-magician]

Hi! I'm the modular magician, I work on Magic Modules.
This PR seems not to have generated downstream PRs before, as of 9f9ca7e.

Pull request statuses

No diff detected in terraform-google-conversion.
No diff detected in Ansible.
No diff detected in Inspec.

New Pull Requests

I built this PR into one or more new PRs on other repositories, and when those are closed, this PR will also be merged and closed.
depends: hashicorp/terraform-provider-google-beta#982
depends: hashicorp/terraform-provider-google#4117

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[chrisst]

CLA doesn't apply to third_party contributions.

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We found a Contributor License Agreement for you (the sender of this pull request), but were unable to find agreements for all the commit author(s) or Co-authors. If you authored these, maybe you used a different email address in the git commits than was used to sign the CLA (login here to double check)? If these were authored by someone else, then they will need to sign a CLA as well, and confirm that they're okay with these being contributed to Google.
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