Update server TLS example to showcase how to extract connection information (#3023)

Showcase how to pass TLS derived information to server operation
handlers, like the certificate chain presented by the client.

To test, run `RUST_LOG=pokemon_service_tls=DEBUG cargo run` and `curl -v
--insecure https://localhost:13734/do-nothing`. Alternatively, run the
tests using `RUST_LOG=pokemon_service_tls=DEBUG cargo test`, which have
been updated to hit the operation that logs the TLS connection derived
information.

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