Bump golang to 1.21

[Neo2308]

• Use go 1.21
• Start running tests on go 1.21
• Stop running tests on go 1.19
• Update setup-go action to v3
• Update checkout action to v3 (missed from Update actions/checkout to v3 #3324)

[google-cla]

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[k8s-ci-robot]

Hi @Neo2308. Thanks for your PR.

I'm waiting for a google 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.

I understand the commands that are listed here.

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.

[iwankgb]

/ok-to-test

[Neo2308]

@iwankgb I seem to have requested a review from you again by mistake, but that is now blocking the PR. Could you take a look? My apologies for the inconvenience.

[iwankgb]

@Neo2308, can you merge master, please?

[Neo2308]

@iwankgb done ✅

[Neo2308]

@iwankgb any pointers on what to do next?

[iwankgb]

@Neo2308, you have to set DEBIAN_FRONTEND.

[bobbypage]

Bumped in #3474; Adjusted that PR to 1.22. Thanks again @Neo2308 for the help!