compute_region_commitment

[modular-magician]

fixes hashicorp/terraform-provider-google#6734

this resource cannot be deleted, and lasts for a year+ which makes testing difficult in CI. I've tested locally and will request a manual removal of all CUDs created in my test project. Logs of successful test runs will be sent to the reviewer.

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`google_compute_region_commitment`

Derived from GoogleCloudPlatform/magic-modules#7521