Backport of Add TCP TLS guide into release/1.16.x

[hc-github-team-secure-vault-core]

Backport

This PR is auto-generated from #27318 to be assessed for backporting due to the inclusion of the label backport/1.16.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:
@jonathanfrappier
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: POST https://api.github.com/repos/hashicorp/vault/merges: 409 Merge conflict []

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

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Based on https://docs.google.com/document/d/1PdFgxbgAd2BA4JNLWSRNmE6laX6zpDSlip-4C41e9r8/edit

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Overview of commits

• ef10c1a

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[github-actions]

CI Results:
All Go tests succeeded! ✅

[github-actions]

Build Results:
All builds succeeded! ✅

[schavis]

Created manual backport PR: #27371