Hello @ttherouanne,
Thanks for bringing this to our notice. We have the fix for this as part of Bug #29449: Minor fixes for developing for pulp3 - Katello - Foreman that is part of 3.16.
I do think it makes sense to cherry-pick this into 3.15. I will un-triage the bug and discuss within the team and get their thoughts on this in 3.15.2.