Auth0 provider doesn't attribute all the values to goth.User

Nobody has claimed this yet.

Hey,

so I noticed that Auth0 is sending some more data back, e.g:

```json
{
"email": "email@example.com",
"email_verified": true,
"family_name": "Example",
"given_name": "Example",
"locale": "en",
"name": "Example Example",
"nickname": "example.example",
"picture": "",
"sub": "google id or other provider id",
"updated_at": "2021-10-21T08:52:15.784Z"
}

```

but the provider seems to be reading only [these values](https://github.com/markbates/goth/blob/master/providers/auth0/auth0.go#L35):
```golang
type auth0UserResp struct {
Name string `json:"name"`
NickName string `json:"nickname"`
Email string `json:"email"`
UserID string `json:"sub"`
AvatarURL string `json:"picture"`
}
```

I want to know if other values, such as **family_name** or **given_name** are not parsed on purpose because they can be left empty by **Auth0** or if it was just overlooked?

Start in providers/auth0/auth0.go at auth0UserResp and trace how its fields are assigned to goth.User. Check the goth.User definition to see which requested Auth0 values it can represent. Done means the agreed fields are mapped consistently, with coverage added wherever the existing Auth0 provider tests support it.

Written by the indexing model from the issue text.