refactor(HomeController): remove culture binding as viewdata; bind via string localizer

EnvelopeGenerator.Web/Views/Home/EnvelopeRejected.cshtml

@@ -10,7 +10,6 @@
 @using Newtonsoft.Json.Serialization
 @model EnvelopeReceiverDto;
 @{
-	var userCulture = ViewData["UserCulture"] as Culture;
 	var envelope = Model.Envelope;
 	var document = Model.Envelope?.Documents?.FirstOrDefault();
 	var sender = Model.Envelope?.User;