Report parameter for date allows entering stand and end values for the range, for example "is between '12/04/2018' and '12/04/2018'". When both values are set to the same day, no results are returned in report.
From the example, both '12/04/2018' values are actually queried from database as 12/04/2018 00:00:00.
For now, please use the next day for date range. This will give you the result you need.
The example for 12/04/2018 results: "is between '12/04/2018' and '13/04/2018'"
This issue has been resolved in Workflow/ServiceDesk 8.5 and newer.