Update local_stream.conf.lua

Set a default rate for chime list if one is not provided.

resources/install/scripts/app/xml_handler/resources/scripts/configuration/local_stream.conf.lua

@@ -39,6 +39,9 @@
 
 		--set the rate
 		rate = row.music_on_hold_rate;
+		if (rate ~= nil or rate == '') then
+			rate = '48000';
+		end
 
 		--add the full path to the chime list
 		chime_list = row.music_on_hold_chime_list;