jupyter-scheduler's endpoint is missing authentication

Jupyter Scheduler is collection of extensions for programming jobs to run now or run on a schedule. The list of conda environments of `jupyter-scheduler` users maybe be exposed, potentially revealing information about projects that a specific user may be working on. This vulnerability has been patched in version(s) 1.1.6, 1.2.1, 1.8.2 and 2.5.2.