gh-95816: Fix TLS version range example in docs

[janbrasna]

There have been a few updates of the wording and the code snipped in the past, leading to the two not matching each other, even after attempts to fix.

This adds back an explicit lower and upper constraint, and fixes the description to match its example.

(Also tweaks one grammar in the neighborhood.)

This also resolves #93798 by superseding it with different approach, and closes #107273 that's linked to already closed issue.

• Issue: Example requires exactly TLSv1.3, but explanation says TLSv1.2 and later #95816

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