Add `authenticatorDisplayName` to Step 27 and Step 23 of the registration and authentication ceremonies respectively

[zacknewman]

#1880 added the optional item authenticatorDisplayName to Credential Record; however it was not added to Step 27 of the registration ceremony nor Step 23 of the authentication ceremony. Seeing how attestationObject and attestationClientDataJSON exist in Step 27, it would be nice to also add authenticatorDisplayName. Honestly, I was under the impression authenticatorDisplayName was only a credProps thing; had it existed in the ceremony criteria section for data to store, I don't think I would have made that mistake.

Something like below would be nice:

The new credential record MAY also include the following OPTIONAL contents:

attestationObject

  response.attestationObject.

attestationClientDataJSON

  response.clientDataJSON.

authenticatorDisplayName

  clientExtensionResults.credProps.authenticatorDisplayName or RP-provided value.