Validation for required case development custom fields is not triggered after hitting Save or Save&Close on Epics

Issue Summary

No error is thrown when users are saving epics with a required custom field set left empty.

Steps to Reproduce

1. Create a custom field set following the help page: https://help.jiraalign.com/hc/en-us/articles/115000370713-10X-Create-Custom-Field-Sets
   Make sure to:
   a- mark the custom field set (of type text or dropdown) as required
   
   b- select it in Case Development Custom Fields dropdown list of your program under Administration>Programs
   

1. Create a new epic and save it or open an existing one.
2. Go to the Benefits tab and scroll to the required field corresponding to the custom field created in step 1.
3. Leave the required field empty or without selecting anything if it is a dropdown field.
4. Hit the Save or Save&Close button

Expected Results

The save fails with the error: Select a <name of the custom set field> (e.g. FXPCustomDropdownRequiredField)

Actual Results

The save succeeds without any error

Workaround

Currently there is no known workaround for this behavior. A workaround will be added here when available