Enable Helm chart to reuse existing TLS secrets

[oliviassss]

Issue

#2239

Description

Enable Helm chart to reuse existing TLS secrets.

Tests

1. Tested the condition when helm upgrade without any configuration, verified that it will auto generate new cert & key.
2. Tested the condition when cert & key are specified in values, they will be used in secret.
3. Tested the condition when user specifies to reuse existing TLS secrets by set keepTLSSecret: true in values, the existing secret is reused in new chart.

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.

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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.

[codecov-commenter]

Codecov Report

Merging #2264 (6b664e5) into main (1eb373b) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##             main    #2264   +/-   ##
=======================================
  Coverage   53.55%   53.55%           
=======================================
  Files         136      136           
  Lines        7607     7607           
=======================================
  Hits         4074     4074           
  Misses       3217     3217           
  Partials      316      316           

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[kishorj]

/ok-to-test

[kishorj]

/retest

[kishorj]

/lgtm

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

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

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• OWNERS [kishorj]

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