Stop using fixed IP in default subnetwork in service attachment example

[rileykarson]

This should help stop some VCR failures

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Release Note Template for Downstream PRs (will be copied)

[modular-magician]

Hi! I'm the modular magician. Your PR generated some diffs in downstreams - here they are.

Diff report:

Terraform GA: Diff ( 2 files changed, 2 deletions(-))
Terraform Beta: Diff ( 5 files changed, 4 insertions(+), 5 deletions(-))
TF OiCS: Diff ( 1 file changed, 1 deletion(-))

[modular-magician]

Hi! I'm the modular magician. Your PR generated some diffs in downstreams - here they are.

Diff report:

Terraform GA: Diff ( 3 files changed, 4 deletions(-))
Terraform Beta: Diff ( 5 files changed, 3 insertions(+), 6 deletions(-))
TF OiCS: Diff ( 1 file changed, 1 deletion(-))

[rileykarson]

/gcbrun

[modular-magician]

Hi! I'm the modular magician. Your PR generated some diffs in downstreams - here they are.

Diff report:

Terraform GA: Diff ( 3 files changed, 4 deletions(-))
Terraform Beta: Diff ( 3 files changed, 4 deletions(-))
TF OiCS: Diff ( 1 file changed, 1 deletion(-))

[modular-magician]

I have triggered VCR tests in RECORDING mode for the following tests that failed during VCR: TestAccComputeServiceAttachment_serviceAttachmentBasicExample|TestAccComputeServiceAttachment_serviceAttachmentBasicExampleUpdate You can view the result here: https://ci-oss.hashicorp.engineering/viewQueued.html?itemId=207136

[slevenick]

Why is this causing problems? Multiple of these tests relying on the same IP that the API doesn't like?

[rileykarson]

They're using the default network/subnetwork to avoid spending extra networks quota where it isn't needed, and if the tests run at the same time they pick the same fixed address. That didn't happen at first, which is why it didn't cause a problem! (Also, I think the tests were written at different times so I think they had no way of conflicting in VCR until both failed)