fix: Length of undefined on users warnings

[franciscofsales]

Description

On my instance, I was getting a frontend error where the were some issues with trying to check the length of undefined.
I tracked it down to a function that was not completely checking its dependencies and just added a more extensive check that should prevent this issue from happening again.

I didn't find anyone else with the same issue but regardless, this PR is a tiny improvement.

This PR does not change any functionality or affect any of the existing ones

Screenshot (if UI-related)

To-Dos

N/A

Issues Fixed or Closed

Could not find anyone experiencing the same issue.

[gauthier-th]

Could you tell use how to reproduce this issue?

[franciscofsales]

Sure, so I run it in the a kuberetes cluster and there's a custom ingress and error handler, this issue happens when the /api/v1/auth/me request does not return the expected 403 response and instead returns something else, which was my cause given that I run https://github.com/tarampampam/error-pages on my setup

[gauthier-th]

lgtm