Google Container Filesystem (GCFS) configuration support

[modular-magician]

Google Container Filesysem (GCFS) recently went GA and GcfsConfig is now available with the release of google-api-go-client v0.60.0:
https://github.com/googleapis/google-api-go-client/releases/tag/v0.60.0

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• [ X] 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).
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• [X ] Ran relevant acceptance tests (If the acceptance tests do not yet pass or you are unable to run them, please let your reviewer know).
• [X ] Read the Release Notes Guide before writing my release note below.

Release Note Template for Downstream PRs (will be copied)

container: added `gcfs_config` to `node_config` of `google_container_node_pool` resource

Derived from GoogleCloudPlatform/magic-modules#5398