DeliveryConfirmation: Do not print sender by default

Elwig/Documents/DeliveryConfirmation.cs

@@ -20,7 +20,6 @@ namespace Elwig.Documents {
             Season = ctx.Seasons.Find(year) ?? throw new ArgumentException("invalid season");
             ShowDateAndLocation = true;
             UseBillingAddress = true;
-            IncludeSender = true;
             DocumentId = $"Anl.-Best. {Season.Year}/{m.MgNr}";
             Data = data;
             MemberBuckets = ctx.GetMemberBuckets(Season.Year, m.MgNr).GetAwaiter().GetResult();