4.0 - Fully remove workload_metadata_config.node_metadata

[modular-magician]

Fixes #8593

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Release Note Template for Downstream PRs (will be copied)

container: removed `workload_metadata_configuration.node_metadata` in favor of `workload_metadata_configuration.mode` in `google_container_cluster`

Derived from GoogleCloudPlatform/magic-modules#5346

[github-actions]

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