Jobs: add check for file age

Jobs/ZUGFeRD/WorkerArgs.vb

@@ -21,6 +21,7 @@ Public Class WorkerArgs
     Public ExceptionEmailAddress As String = Nothing
     Public IgnoreRejectionStatus As Boolean = False
     Public MaxAttachmentSizeInMegaBytes As Integer = -1
+    Public MinFileAgeInMinutes As Integer = 5
     Public NamePortal As String = "NO PORTAL_NAME IN CONFIG"
 
     Public AllowFacturX As Boolean = True