Added deinit() to play_file, stop_tone

Author: kattni

adafruit_circuitplayground/express.py

@@ -649,6 +649,8 @@ def stop_tone(self):
         # Stop playing any tones.
         if self._sample is not None and self._sample.playing:
             self._sample.stop()
+            self._sample.deinit()
+            self._sample = None
         self._speaker_enable.value = False
 
     def play_file(self, file_name):
@@ -677,6 +679,7 @@ def play_file(self, file_name):
             audio.play(file)
             while audio.playing:
                 pass
+            audio.deinit()
         else:
             audio = audioio.AudioOut(board.SPEAKER, open(file_name, "rb"))
             audio.play()