improve list generation

ref: https://stackoverflow.com/questions/66430961/is-there-a-way-to-use-the-list-output-from-a-jinja2-range-function-directly-in

templates/startup.scd.template

@@ -31,7 +31,7 @@ s.reboot { // server options are only updated on reboot
 {% if sc_option_numOutputBusChannels == 2 %}
 		~dirt.start(57120, 0 ! 12);   // start listening on port 57120, create two busses each sending audio to channel 0
 {% else %}
-		~dirt.start(57120, [{% for i in range(0, sc_option_numOutputBusChannels, 2 ) %}{{ i }}{% if i != sc_option_numOutputBusChannels - 2 %}, {%endif %}{% endfor %}]);   // start listening on port 57120, create {{ (sc_option_numOutputBusChannels/2)|int }} stereo busses
+		~dirt.start(57120, {{ range(0, sc_option_numOutputBusChannels, 2 ) | list }} );   // start listening on port 57120, create {{ (sc_option_numOutputBusChannels/2)|int }} stereo busses
 {% endif %}
 
         // optional, enable feedforward vu meter