TPT-4368: Update integration tests due to deprecated "vpcs" for NB create

[mawilk90]

📝 Description

Changes related to the fact that "vpcs" attribute is deprecated (but still valid) in favor of "backend_vpcs" in POST /nodebalancers

✔️ How to Test

Without fixtures:
go test -count=1 ./test/integration/ -v -run TestNodeBalancer_Create_With

With fixtures:
make test-int TEST_ARGS="-run TestNodeBalancer_Create_With"

[dawiddzhafarov]

LGTM and tests pass!

[Copilot]

Pull request overview

Updates Linodego integration tests/fixtures to account for the deprecation of the vpcs field on NodeBalancer create requests in favor of backend_vpcs, while also adding coverage to ensure the deprecated field remains accepted for now.

Changes:

• Updated NodeBalancer integration test setup helpers to send backend_vpcs instead of vpcs.
• Refreshed integration fixtures to match the new request payloads (backend_vpcs) and updated recorded responses.
• Added a new integration test + fixture to validate the deprecated vpcs create attribute is still accepted.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 3 comments.

File	Description
test/integration/nodebalancers_test.go	Switches create options to BackendVPCs in helpers; adds a new test for deprecated VPCs usage.
test/integration/fixtures/TestNodeBalancer_Create_WithFrontendAndBackendInDifferentVPCs.yaml	Updates recorded POST body from vpcs to backend_vpcs (plus re-recorded fixture deltas).
test/integration/fixtures/TestNodeBalancer_Create_WithDeprecatedVPCsAttribute.yaml	New fixture for the deprecated vpcs attribute create path.
test/integration/fixtures/TestNodeBalancer_Create_WithBackendVPCOnly.yaml	Updates recorded POST body from vpcs to backend_vpcs (plus re-recorded fixture deltas).

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

[Copilot]

The failure message has a typo/inaccurate wording: "VPCc attribute" should be "VPCs attribute" (or "vpcs attribute"). This makes failures harder to interpret when the test breaks.

Suggested change

	require.NoErrorf(t, err, "Error creating NodeBalancer with VPCc attribute: %v", err)
	require.NoErrorf(t, err, "Error creating NodeBalancer with VPCs attribute: %v", err)

[Copilot]

This test is meant to validate the deprecated vpcs request field still behaves correctly, but it only asserts the NodeBalancer was created. Please also assert the backend VPC attachment was actually created (e.g., list NodeBalancer VPC configs and check subnet/purpose), otherwise a regression that silently ignores vpcs could still pass.

[Copilot]

The comment has an odd leading tab and reads like a sentence fragment ("//\tTo test..."). Please reformat it as a standard Go comment sentence (single space after //, capitalized) for readability and consistency.

Suggested change

	// To test that deprecated VPCs attribute is still valid - it will be deleted when it can no longer be used
	// Test that the deprecated VPCs attribute is still valid; it will be deleted when it can no longer be used.

[ezilber-akamai]

I get this error:

    nodebalancers_test.go:143: 
                Error Trace:    /Users/ezilber/Projects/dx-devenv/repos/linodego/test/integration/nodebalancers_test.go:566
                                                        /Users/ezilber/Projects/dx-devenv/repos/linodego/test/integration/nodebalancers_test.go:143
                Error:          Received unexpected error:
                                [400] [type] User doesn't have permissions to add the requested type of NodeBalancer
                Test:           TestNodeBalancer_Create_WithFrontendVPCOnly
                Messages:       Error listing nodebalancers, expected struct, got error [400] [type] User doesn't have permissions to add the requested type of NodeBalancer

despite having (I think) all required customer tags on my account.