live transmission: added modulation to yaml output

gr_grc/scripts/show_live_transmissions.py

@@ -191,6 +191,7 @@ def main(top_block_cls=top_block, options=None):
             transmission['last_one'] = last_one
             transmission['transmission_time'] = transmission_time
             transmission['real_transmission_time'] = real_transmission_time
+            transmission['modulation'] = modulation
 
             signal_blocks.append(transmission)
             output['signal_blocks'] = signal_blocks