Deprecate node_metadata and add mode

[modular-magician]

Part of #8593

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• Searched through the issue tracker for an open issue that this either resolves or contributes to, commented on it to claim it, and written "fixes {url}" or "part of {url}" in this PR description. If there were no relevant open issues, I opened one and commented that I would like to work on it (not necessary for very small changes).
• Generated Terraform, and ran make test and make lint to ensure it passes unit and linter tests.
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• Read the Release Notes Guide before writing my release note below.

Release Note Template for Downstream PRs (will be copied)

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

container: added support for `workload_metadata_configuration.mode` in `google_container_cluster`

Derived from GoogleCloudPlatform/magic-modules#5259

[github-actions]

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