Actually enable TLSv1.3 by default

[praseodym]

What this PR does / why we need it:

Fix for 049b25e (#5358) which mistakenly only updated documentation.

Types of changes

New feature (non-breaking change which adds functionality)

How Has This Been Tested?

Tested these settings using the settings ConfigMap.

Checklist:

• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I've read the CONTRIBUTION guide
• I have added tests to cover my changes.
• All new and existing tests passed.

[k8s-ci-robot]

Hi @praseodym. 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.

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[ElvinEfendi]

I'm OK with enabling TLSv1.3 by default since we have ssl_early_data off by default too. However we should edit the documentation in https://github.com/kubernetes/ingress-nginx/blob/master/docs/user-guide/nginx-configuration/configmap.md#ssl-early-data and include a warning that enabling ssl_early_data (0-RTT) exposes the server for reply attacks as explained in https://blog.cloudflare.com/introducing-0-rtt/ ("What's the catch section") . cc @wayt

[praseodym]

@ElvinEfendi I've added a warning based on the text in the ssl_early_data nginx docs.

[ElvinEfendi]

/lgtm

[ElvinEfendi]

/ok-to-test

[codecov-io]

Codecov Report

Merging #5491 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #5491   +/-   ##
=======================================
  Coverage   58.56%   58.56%           
=======================================
  Files          88       88           
  Lines        6948     6948           
=======================================
  Hits         4069     4069           
  Misses       2431     2431           
  Partials      448      448           

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[praseodym]

/retest

[praseodym]

/retest

[praseodym]

/retest

[praseodym]

@ElvinEfendi Had to fix a test, could you review this again? Thanks!

[aledbf]

/lgtm

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: aledbf, ElvinEfendi, praseodym

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• OWNERS [ElvinEfendi,aledbf]

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