Fix Auth0 Example

[stevejarvis]

Fixes #31286

I was going through the Auth0 example and hit the following issue (screencap):

This just updates the call there to pass res, which matches the signature documented here: https://auth0.github.io/nextjs-auth0/modules/session_get_session.html

With this fix, the rest of the example worked wonderfully 👍.

Bug

• Related issues linked using fixes #number
• Integration tests added (NA?)
• Errors have helpful link attached, see contributing.md

[leerob]

Thank you!