revise PyPortal_Smart_Thermometer theremometer_helper.py to be compatible with CP 5.x

Author: jerryneedell

PyPortal_Smart_Thermometer/thermometer_helper.py

@@ -29,11 +29,9 @@ def __init__(self, celsius=True, usa_date=True):
 
         # create background icon group
         self._icon_group = displayio.Group(max_size=1)
-        self.append(self._icon_group)
         board.DISPLAY.show(self._icon_group)
         # create text object group
         self._text_group = displayio.Group(max_size=6)
-        self.append(self._text_group)
 
         self._icon_sprite = None
         self._icon_file = None
@@ -143,6 +141,4 @@ def set_icon(self, filename):
                                                    position=(0,0))
 
         self._icon_group.append(self._icon_sprite)
-        board.DISPLAY.refresh_soon()
-        board.DISPLAY.wait_for_frame()
-  
+