Enable krel gcbmgr package and binary checks

[saschagrunert]

What type of PR is this?

/kind feature

What this PR does / why we need it:

We re-enable the commented out binary and package checks because the
packages are now available in the CI.

Which issue(s) this PR fixes:

None

Special notes for your reviewer:

Needs: #1170

Does this PR introduce a user-facing change?:

- Changed `krel gcbmgr` to check for available packages (jq, git, bsdmainutils) and binaries (gsutil, gcloud) on the host system

[k8s-ci-robot]

@saschagrunert: Adding label: do-not-merge/blocked-paths because PR changes a protected file.

Reasons for blocking this PR:

[Changes to certain release tools can affect our ability to test, build, and release Kubernetes. This PR must be explicitly approved by SIG Release repo admins.]

• cmd/krel/cmd/gcbmgr.go

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.

[justaugustus]

/hold until rebased on #1170

[justaugustus]

Ready to be rebased now that #1170 has merged.

[saschagrunert]

Rebased on top of the latest master branch

[saschagrunert]

Needs #1206

[justaugustus]

/retest

[saschagrunert]

Tests are green, I think we should not rely on check for dedicated packages (see the jq change in this PR), where an appropriate check for a binary in $PATH seems more flexible to me.

[justaugustus]

@saschagrunert -- Feel free to handle in a follow-up! :)
/lgtm
/approve

[justaugustus]

Looks like I accidentally removed the lgtm 😅
/lgtm

[cpanato]

/lgtm

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: cpanato, justaugustus, saschagrunert

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• cmd/krel/OWNERS [justaugustus,saschagrunert]

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