ekanban breaks redmine_helpdesk plugin

[kaazoo]

Once the ekanban plugin is installed, the email to ticket import of the redmine_helpdesk plugin (see https://github.com/jfqd/redmine_helpdesk) doesn't work anymore.

rake -f Rakefile redmine:email:receive_imap generates no tickets.

[teadur]

I stumbled on the same issue, the problem is that ekanban implements assigned to validation but that brakes redmine_helpdesk because it tries to create issue without assigned to.