Add support for image type configuration on the GKE NAP

[modular-magician]

Since one of the image streaming requirements is having Container-Optimized OS with containers as node image and on the other side, if we use the Node Auto Provisioning, there's not any possibility to config auto_provisioning_defaults to set up the default image type to cos_containerd.
In this PR I added this feature to pass the image_type value on the NAP configuration.

Related issue: #10957

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Release Note Template for Downstream PRs (will be copied)

container: Added support for image type configuration on the GKE Node Auto-provisioning

Derived from GoogleCloudPlatform/magic-modules#5644

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