Update argument name in examples.

Author: kattni

examples/dash_display_advancedtest.py

@@ -196,7 +196,7 @@ def pub_lamp(lamp):
 # Initialize an Adafruit IO MQTT Client
 io = IO_MQTT(mqtt_client)
 
-iot = Hub(display=display, io=io, nav=(up, select, down, back, submit))
+iot = Hub(display=display, io_mqtt=io, nav=(up, select, down, back, submit))
 
 iot.add_device(
     feed_key="lamp",

examples/dash_display_simpletest.py

@@ -69,7 +69,7 @@ def pub_lamp(lamp):
     time.sleep(0.3)
 
 
-iot = Hub(display=display, io=io, nav=(up, select, down, back, submit))
+iot = Hub(display=display, io_mqtt=io, nav=(up, select, down, back, submit))
 
 iot.add_device(
     feed_key="lamp",