kubeadm: Parse ENV vars to crictl command

[mk46]

What type of PR is this?

/kind bug

What this PR does / why we need it:

Parse ENV vars to crictl command

Which issue(s) this PR fixes:

Fixes kubernetes/kubeadm#2697

Special notes for your reviewer:

Does this PR introduce a user-facing change?

kubeadm: pass the host OS environment variables when executing "crictl" during image pulls. This fixes a bug where *PROXY environment variables did not affect crictl's internet connectivity.

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

[k8s-ci-robot]

Hi @mk46. Thanks for your PR.

I'm waiting for a kubernetes 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.

Once the patch is verified, the new status will be reflected by the ok-to-test label.

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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.

[mk46]

/cc @neolit123

[neolit123]

thanks @mk46

/lgtm
/approve
/triage accepted
/ok-to-test
/priority backlog

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: mk46, neolit123

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• cmd/kubeadm/OWNERS [neolit123]

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[neolit123]

/release-note-edit

kubeadm: pass the host OS environment variables when executing "crictl" during image pulls. This fixes a bug where *PROXY environment variables did not affect crictl's internet connectivity.