Latest Items Component property "constraint" should not be mandatory

This applies to only four components:
Latest comments, Latest events, Jobs, Latest reviews

As admin, login to CMS >> Navigate to Channel Manager >> Select English website (any channel) >> Click edit template >> then

1. Click on the Jobs content >> Latestjob properties with persona's is shown
2. Enter some junk value in "Constraint" field and click on "Save" button

Expected - It should thrown an error
Actual - The junk value does not have any effect (refer screenshot)
Moreover this field is shown as mandatory field (refer screenshot1)