Fix the bug that kubectl convert does not pick the right api version

[SataQiu]

What type of PR is this?

/kind bug

What this PR does / why we need it:

Fix the bug that kubectl convert does not pick the right api version

Which issue(s) this PR fixes:

Fixes kubernetes/kubectl#1298

Special notes for your reviewer:

Does this PR introduce a user-facing change?

kubectl: fixed a bug where `kubectl convert` did not pick the right API version

Additional documentation e.g., KEPs (Kubernetes Enhancement Proposals), usage docs, etc.:

[aojea]

/assign @deads2k @soltysh

[SataQiu]

/test pull-kubernetes-e2e-gce-ubuntu-containerd

[soltysh]

This indeed ensures the extensions API is considered the last when decoding and reading the default option, you can still explicitly request it with --output-version=extensions/v1beta1

/lgtm
/approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: SataQiu, soltysh

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• pkg/kubectl/OWNERS [soltysh]

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[soltysh]

/triage accepted
/priority backlog

[sftim]

Hope this is OK:

/release-note-edit

kubectl: fixed a bug where `kubectl convert` did not pick the right API version

[k8s-ci-robot]

@sftim: /release-note-edit must be used with a release note block.

In response to this:

Hope this is OK:

/release-note-edit

kubectl: fixed a bug where `kubectl convert` did not pick the right API version

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository.

[sftim]

/release-note-edit

kubectl: fixed a bug where `kubectl convert` did not pick the right API version

[k8s-ci-robot]

@sftim: /release-note-edit must be used with a release note block.

In response to this:

/release-note-edit

kubectl: fixed a bug where `kubectl convert` did not pick the right API version

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository.

[sftim]

OK, not sure about the command but that's the change I recommend.

[liggitt]

Thanks for the PR... one thing to note is that relying on import order is fragile… this preferred order should be set explicitly (and a unit test added to cover this scenario so it doesn't regress)