Automatic merge from submit-queue

Include all user.Info data in CSR object

In order to use authorization checks to auto-approve CSRs in the future, we need all the info from the user.Info interface.

This mirrors the API fields in the TokenReview API used to return user info, and in the SubjectAccessReview API we use to check authorization.

```release-note
The CertificateSigningRequest API added the `extra` field to persist all information about the requesting user. This mirrors the fields in the SubjectAccessReview API used to check authorization.
```