Update shebang line for update_device.py. am: 0c71550bf3

Original change: https://android-review.googlesource.com/c/platform/system/update_engine/+/1679889

Change-Id: Ia60ffa8c9c9d98b234ab7a20157e0957dd3ab654
diff --git a/scripts/update_device.py b/scripts/update_device.py
index 7313d7c..f672cda 100755
--- a/scripts/update_device.py
+++ b/scripts/update_device.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 #
 # Copyright (C) 2017 The Android Open Source Project
 #