Don't clear all output in `auth.authenticate_user()`.
Don't clear all output in `auth.authenticate_user()`.

We originally cleared all output because we didn't support temporary output
tags; now that we do, this is a quick cleanup.

Before: http://screen/QEmgXK8NdGH
After: http://screen/zXTK3EXbCgR

RELNOTES: n/a
Build log: n/a
PiperOrigin-RevId: 208678051

googlecolab/colabtools,googlecolab/colabtools