Add support for capacity aware modes to `google_compute_region_instance_group_manager

[modular-magician]

Fixes: hashicorp/terraform-provider-google#8002

You also need to bump the API library to v0.36.

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Release Note Template for Downstream PRs (will be copied)

compute: added `distribution_policy_target_shape` field to `google_compute_region_instance_group_manager` resource

Derived from GoogleCloudPlatform/magic-modules#4348