remove IsUnstructuredCRDReady

[reasonerjt]

Please add a summary of your change

This commit removes IsUnstructuredCRDReady since
kubernetes/kubernetes#87675 is fixed.
It uses Is1CRDReady to check the readiness of CRD.

After v1.7 we may consider merge the funcx IsV1Beta1CRDReady and
IsV1CRDReady

Does your change fix a particular issue?

Fixes #4059

Please indicate you've done the following:

• Accepted the DCO. Commits without the DCO will delay acceptance.
• Created a changelog file or added /kind changelog-not-required.
• Updated the corresponding documentation in site/content/docs/main.

[zubron]

LGTM - thanks! I'll approve again once the CI check is green (looks like a go fmt issue).

[jenting]

The upstream fixes this issue at Kubernetes 1.20+?
If yes, will this change impact the user using the Kubernetes < 1.20 to do restore?

[reasonerjt]

The upstream fixes this issue at Kubernetes 1.20+?
If yes, will this change impact the user using the Kubernetes < 1.20 to do restore?

@jenting
I think the fix is in the code that is compiled in velero binary.
It was fixed due to the bump up introduced by #4022
More specifically https://github.com/vmware-tanzu/velero/pull/4022/files#diff-33ef32bf6c23acb95f5902d7097b7a1d5128ca061167ec0716715b0b9eeaa5f6L42-R41

So the version of k8s that velero server runs on should be irrelevant

[jenting]

The upstream fixes this issue at Kubernetes 1.20+?
If yes, will this change impact the user using the Kubernetes < 1.20 to do restore?

@jenting
I think the fix is in the code that is compiled in velero binary.
It was fixed due to the bump up introduced by #4022
More specifically https://github.com/vmware-tanzu/velero/pull/4022/files#diff-33ef32bf6c23acb95f5902d7097b7a1d5128ca061167ec0716715b0b9eeaa5f6L42-R41

So the version of k8s that velero server runs on should be irrelevant

Okay, it's like fixed in k8s.io/apimachinery in 0.20.x version.
Good to know, thank you.

[jenting]

Thank you for removing this workaround.

[sseago]

@jenting Also, the associated test should fail if we ever pull in a version of kubernetes code without the fix -- the reproducing test was added when moving to the unstructured workaround.