Tidy - remove thread count in synth log

Author: samaaron

app/server/ruby/lib/sonicpi/lang/sound.rb

@@ -3564,7 +3564,7 @@ def trigger_inst(synth_name, args_h, info=nil, group=current_group)
 
 
         unless __thread_locals.get(:sonic_pi_mod_sound_synth_silent)
-          __delayed_message "[#{Thread.list.size}] synth #{synth_name.inspect}, #{arg_h_pp(processed_args)}"
+          __delayed_message "synth #{synth_name.inspect}, #{arg_h_pp(processed_args)}"
         end
 
         add_arg_slide_times!(processed_args, info) if info