CI and Go updates

[cpanato]

What type of PR is this?

/kind cleanup

What this PR does / why we need it:

• ci cleanup and updates
• go bump to 1.21.9

/assign @richardcase @damdo

Which issue(s) this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close the issue(s) when PR gets merged):
Fixes #

Special notes for your reviewer:

Please confirm that if this PR changes any image versions, then that's the sole change this PR makes.

TODOs:

• squashed commits
• includes documentation
• adds unit tests

Release note:

- ci cleanup and updates
- go bump to 1.21.9

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: cpanato

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• OWNERS [cpanato]

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[damdo]

Thanks
/lgtm