Update error message for missing channel IDs

DiscordChatExporter.Cli/Commands/ExportChannelsCommand.cs

@@ -59,7 +59,7 @@ public partial class ExportChannelsCommand : ExportCommandBase
         {
             throw new CommandException(
                 "No channel IDs provided. "
-                    + "Specify channel IDs as arguments or pipe them from the 'list channels' or 'list channels dm' commands."
+                    + "Specify channel IDs as arguments or pipe them from a newline-separated list."
             );
         }