Properly unwrap gce-compute error code.

[hime]

What type of PR is this?

Uncomment only one /kind <> line, hit enter to put that in a new line, and remove leading whitespaces from that line:

/kind api-change

/kind bug

/kind cleanup
/kind design
/kind documentation
/kind failing-test
/kind feature
/kind flake

What this PR does / why we need it:
A new way of wrapping errors was introduced in compute engine API (eg. "cloud.service.Disks.Insert") where some of these errors are wrapped with an additional layer of googleapi.Error. This additional wrap does not contain the http error code in its error code field, but instead contains a default value of Unknown. This is problematic because one of the ways we extract errors is by checking if the error can be a status (signifying a temporary error instead). The way the error is structured allows it to be classified as temporary, which causes our code to return the Unknown error present in the outermost layer, before any other error checks occur.

This has been causing issues in how we report errors coming from compute engine, since we do not currently unwrap them properly, resulting in Unknown error code being reported in most scenarios. This PR ensures we are unwrapping the embedded error code properly while making sure all the other error types we encounter continue to process errors as expected.

Which issue(s) this PR fixes:
Fixes #

Special notes for your reviewer:

Does this PR introduce a user-facing change?:

Error codes extracted from errors part of compute engine api are now exposed with correct http errors instead of being classified as Unknown.

[linux-foundation-easycla]

The committers listed above are authorized under a signed CLA.

• ✅ login: hime / name: Jaime (384acf8)

[k8s-ci-robot]

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[k8s-ci-robot]

Hi @hime. Thanks for your PR.

I'm waiting for a kubernetes-sigs member to verify that this patch is reasonable to test. If it is, they should reply with /ok-to-test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work. Regular contributors should join the org to skip this step.

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[amacaskill]

/ok-to-test

[hime]

/test pull-gcp-compute-persistent-disk-csi-driver-kubernetes-integration

[mattcary]

Please add a release not -- it will make backporting of this change a lot easier. Thanks!

[amacaskill]

/test pull-gcp-compute-persistent-disk-csi-driver-kubernetes-integration

[hime]

/retest

[amacaskill]

/retest

[amacaskill]

/lgtm
/approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: amacaskill, hime

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