FIX: add site setting email_site_title, which overrides title in reply by email address in case the title has invalid characters

lib/email/message_builder.rb

@@ -168,7 +168,7 @@ module Email
     end
 
     def site_alias_email(source)
-      "#{SiteSetting.title} <#{source}>"
+      "#{SiteSetting.email_site_title.presence || SiteSetting.title} <#{source}>"
     end
 
   end