PIN set issue with webauthn

[Williams R Milner]

Most users know that the default min PIN length is 4, but the CTAP 2.0 specification allows for a min PIN length that is greater than 4, and in CTAP 2.1 the minPINLength property was added to the authenticatorGetInfo response to allow the platform to get the min PIN length so that it can provide proper UI guidance.

Authenticators that support FIPS 140-3 have a min PIN length requirement of 8, so the UI guidance is very important.