Fix usage of the removed `required` validator for `wtforms`
- instead, we now use the
DataRequired
validator that checks for the presence of a truthy value
*** Wartungsfenster jeden ersten Mittwoch vormittag im Monat ***
DataRequired
validator that checks for
the presence of a truthy value[ 21.Nov 15h : 3,513 users | 843 groups | 4,435 projects ]