[14.0] date_range : date range generator ask for end date even if it's already filled

[abenzbiria]

Module

date_range

Describe the bug

Generate date range wizard raise a Validation Error asking to fill the end date even if it's already done.

To Reproduce

Affected versions: 14

Steps to reproduce the behavior:

1. I fill all required data to generate monthly periods
   

2. I get a validation error message :
   

Expected behavior
The wizad have to generate my periods like bellow :

Additional context
When I set 12 at the entries field , the wizard generate well the periods .