Cloned from https://bugzilla.redhat.com/show_bug.cgi?id=2158524

Description of problem: Input field 'Trusted hosts' is not accepting multiple entries as per the description comma separated input should work.

Version-Release number of selected component (if applicable): 6.13.0 snap 4_0

How reproducible: Always

Steps to Reproduce:
1. Navigate to Administer -> Settings page, switch to tab 'Authentication'
2. Inside input filed of 'Trusted hosts' give multiple valid input comma separated as per maintained in Description.
3. Click submit button and observe error message.

Actual results: Not accepted valid input and showing error "must be comma separated, must contain valid hostnames"

Expected results: Input should accepted and display in list comma separated

Additional info: Attached screenshot related to same.