Backport of values.yaml - tlsServerName docs into release/1.2.x

[hc-github-team-consul-core]

Backport

This PR is auto-generated from #3656 to be assessed for backporting due to the inclusion of the label backport/1.2.x.

🚨

Warning automatic cherry-pick of commits failed. If the first commit failed,
you will see a blank no-op commit below. If at least one commit succeeded, you
will see the cherry-picked commits up to, not including, the commit where
the merge conflict occurred.

The person who merged in the original PR is:
@david-yu
This person should manually cherry-pick the original PR into a new backport PR,
and close this one when the manual backport PR is merged in.

merge conflict error: unable to process merge commit: "427cdd71931073fad9bb04dcfbd1f2a073abf137", automatic backport requires rebase workflow

The below text is copied from the body of the original PR.

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Changes proposed in this PR

• Follow up to https://github.com/hashicorp/consul/pull/18759/files from @maksimnosal

How I've tested this PR

How I expect reviewers to test this PR

Checklist

• Tests added
• CHANGELOG entry added

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Overview of commits

• 1598b40 - 41dabc4 - 427cdd7