Allow specifying node pool cluster as a long-form id

[modular-magician]

This allows users to specify an id-based relationship between the two, which will ensure the node pool is automatically re-created when the cluster is re-created. (This is a core behavior of terraform.)

Resolved hashicorp/terraform-provider-google#9220.

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Release Note Template for Downstream PRs (will be copied)

container: Allowed specifying a cluster id field for `google_container_node_pool.cluster` to ensure that a node pool is recreated if the associated cluster is recreated.

Derived from GoogleCloudPlatform/magic-modules#4842