Additional fixes for stateful ips in (region)_instance_group_manager

[modular-magician]

This fixes an issue omitted during GA promotion: GoogleCloudPlatform/magic-modules#9115, where changes only in stateful_(internal|external)_ip will not trigger a Patch call in the GA provider.
fixes #10908

Also, reenables a test that should no longer flake due to GoogleCloudPlatform/magic-modules#9577
#13430

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Fix issue that changes only in stateful_(internal|external)_ip will not trigger a Patch call in the GA provider for compute_(region_)instance_group_manager

Derived from GoogleCloudPlatform/magic-modules#9965

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