WebAuthn data classes not compatible with JdkSerializationRedisSerializer, and switching to Jackson2 serializer has many issues

[justincranford]

Describe the bug
Persistence of WebAuthn service data objects only seems to work if using in-memory MapSessionRepository.

1. PublicKeyCredentialCreationOptions
2. PublicKeyCredentialRequestOptions

Persistence doesn't work if using RedisSessionRepository.

1. Redis defaultSerializer seems to be JdkSerializationRedisSerializer.
2. WebAuthn data classes in https://github.com/spring-projects/spring-security/tree/fd267dfb71bfc8e1ab5bcc8270c12fbaad46fddf/web/src/main/java/org/springframework/security/web/webauthn/api don't seem to implement the Serializable interface required for JdkSerializationRedisSerializer to work.

To Reproduce
I implemented a repo to:

1. Reproduce and demonstrate the initial RedisSessionRepository JdkSerializationRedisSerializer issue
2. Reproduce and demonstrate all of the issues I encountered, and the incremental workarounds I had to apply, to make the WebAuthn service data classes compatible with RedisSessionRepository JSON Jackson2 serialization

https://github.com/justincranford/spring-security-webauthn-redis

Expected behavior

1. WebAuthn service data classes should work with JdkSerializationRedisSerializer out-of-the-box.
2. WebAuthn service data classes should work with GenericJackson2JsonRedisSerializer out-of-the-box too, or with minimal boilerplate.
3. Examples should be included in official documents for WebAuthn and/or Redis.

Sample
See repo with README
https://github.com/justincranford/spring-security-webauthn-redis