Add support for configuring disk resource policies for google_compute_instance_template

[modular-magician]

Fixes #6719

upstreams #8237

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• Generated Terraform, and ran make test and make lint to ensure it passes unit and linter tests.
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• Read the Release Notes Guide before writing my release note below.

Release Note Template for Downstream PRs (will be copied)

compute: added `disk.resource_policies` field to resource `google_compute_instance_template`

Derived from GoogleCloudPlatform/magic-modules#4463

[ghost]

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