Force-send min_ready_sec

[modular-magician]

Followup to GoogleCloudPlatform/magic-modules#5262, min_ready_sec needs to be force-sent to the API in PATCH to set it to zero. That's different than most GCP APIs which only check patch on the top level.

No changelog needed, this falls under the previous change.

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Release Note Template for Downstream PRs (will be copied)

compute: fixed the `google_compute_instance_group_manager.update_policy.0.min_ready_sec` field so that updating it to `0` works

compute: fixed the `google_compute_region_instance_group_manager.update_policy.0.min_ready_sec` field so that updating it to `0` works

Derived from GoogleCloudPlatform/magic-modules#5402

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