How to get authenticatorSelection field be part of the options returned from req.webAuthn.beginRegistration(user:)

[Joride]

Hey folks, it seems the field authenticatorSelection is not part of the options. When trying out the passkey registration ceremony on https://webauthn.io, I can see that that field is part of it and contains three fields: residentKey, requireResidentKey anduserVerification.
When I test my implementation on an Android device, the I see different behaviour of the browser/OS as compared to the webauthn.io example. Most importantly, the passkey does not seem to be stored on the device for my implementation, and it does get stored for the webauthn.io implementation.
I am not sure why, but my thinking was to mimic the response given by the webauthn.io implementation, starting by adding the authenticatorSelection dictionary to it.
I could have my code insert this after the call to req.webAuthn.beginRegistration(user:), but that seems dirty. Does webauthn-swift have the capability to add the authenticatorSelection dictionary? (And if so, please point me to how get it to do that, I can't seem to find it).

For completeness' sake, these fields are also part of the JSON returned by the webauthn.io example. Which will be next on my list to test out and see if they make a difference in my implementation to get android to store the passkeys:

  "excludeCredentials": [],
  "hints": [],
  "extensions": {
    "credProps": true
  }

[Joride]

Addressed in this PR.