Additional fixes for stateful ips in (region)_instance_group_manager

[askubis]

This fixes an issue omitted during GA promotion: #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 #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

[roaks3]

/gcbrun

[modular-magician]

Hi there, I'm the Modular magician. I've detected the following information about your changes:

Diff report

Your PR generated some diffs in downstreams - here they are.

Terraform GA: Diff ( 3 files changed, 2 insertions(+), 4 deletions(-))
Terraform Beta: Diff ( 1 file changed, 2 deletions(-))

[modular-magician]

Tests analytics

Total tests: 885
Passed tests: 812
Skipped tests: 72
Affected tests: 1

Click here to see the affected service packages

• compute

Action taken

Found 1 affected test(s) by replaying old test recordings. Starting RECORDING based on the most recent commit. Click here to see the affected tests

TestAccRegionInstanceGroupManager_stateful

Get to know how VCR tests work

[modular-magician]

$\textcolor{green}{\textsf{Tests passed during RECORDING mode:}}$
TestAccRegionInstanceGroupManager_stateful[Debug log]

$\textcolor{green}{\textsf{No issues found for passed tests after REPLAYING rerun.}}$

---

$\textcolor{green}{\textsf{All tests passed!}}$
View the build log or the debug log for each test

[roaks3]

LGTM

Just checking, is there an issue filed specifically for this? hashicorp/terraform-provider-google#10908 looks like an older issue that was already marked fixed. It isn't a requirement, but I want to make sure we close any associated bugs if they're out there.

[askubis]

No, there's no new issue, I was cleaning up other functionality (pull/9964) and noticed something omitted with Stateful IPs