Sorting column is by number not date

[gpoo]

Example, in Report user tasks, one can sort the output table by date (asc), and the output could become something like:

• 02/01/2020
• 16/10/2019
• 30/12/2019

The expected output is:

• 16/10/2019
• 30/12/2019
• 02/01/2020