[compute_instance] - Allow updating of network and subnetwork properties

[modular-magician]

Allow updating of network and subnetwork properties on resource_compute_instance.
Some issues of 7118 are fixed. Still need to add support for updating network_ip during subnetwork change. This would require utilizing a customized diff.

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• Read the Release Notes Guide before writing my release note below.

Release Note Template for Downstream PRs (will be copied)

compute: added support for updating `network_interface.[d].network` and `network_interface.[d].subnetwork` properties on `google_compute_instance`.

Derived from GoogleCloudPlatform/magic-modules#4011

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