Remove column "Translation job" from task overview

Remove column "Translation job" from task overview.

Remove also all connected code and DB columns.

Check, if other functionality than the tag check was connected to it and if yes, discuss how to solve this.

For sure connected is the label on the export option for translated/reviewed tasks.

Therefore change it to

EN: Export -> Original format, at current workflow status

DE: Export -> Original Format, im aktuellen Workflowzustand