Accept unknown transports in deserialisation

[Firstyear]

Fixes #364

• [ x ] cargo test has been run and passes
• [ x ] documentation has been updated with relevant examples (if relevant)

[micolous]

Can this have a test for some unknown values?

Also this broke with win10: https://github.com/kanidm/webauthn-rs/actions/runs/6477577093/job/17587986234?pr=367#step:10:129