Upgrade webhook server minimum version to TLS1.3

[oliviassss]

Issue

#2531

Description

Use TLS1.3 as the webhook server minimum version.

Tests

Manually tested on eks cluster with k8s 1.19, verified that TLS1.3 is supported.

Checklist

• Added tests that cover your change (if possible)
• Added/modified documentation as required (such as the README.md, or the docs directory)
• Manually tested
• Made sure the title of the PR is a good description that can go into the release notes

BONUS POINTS checklist: complete for good vibes and maybe prizes?! 🤯

• Backfilled missing tests for code in same general area 🎉
• Refactored something and made the world a better place 🌟

[k8s-ci-robot]

Hi @oliviassss. Thanks for your PR.

I'm waiting for a kubernetes-sigs 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.

[kishorj]

/ok-to-test

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: kishorj, oliviassss

The full list of commands accepted by this bot can be found here.

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• OWNERS [kishorj]

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[oliviassss]

/retest

[kishorj]

/lgtm

[kishorj]

/lgtm