[24.1] Empty Page Object Permissions

[arash77]

Describe the bug
While there is no Page Object yet the Page Object Permissions shows an empty list.

Galaxy Version and/or server at which you observed the bug
Galaxy Version: 24.1.rc1 (test.galaxyproject.org)

Browser and Operating System
Operating System: Linux
Browser: Firefox

To Reproduce
Steps to reproduce the behavior:

1. Go to Pages
2. Create a new empty Page
3. Click on the permissions icon on the top right (users logo)
4. See the table headers

Expected behavior
Show an alert that there is no Page Object added yet.

Screenshots