Update ktlint.py hashbang to Python 3 am: e0287ddf91

Original change: https://android-review.googlesource.com/c/platform/prebuilts/ktlint/+/1889435

Change-Id: Ia0074d2988063f0ad6b1501bcb9fc6d6274eede4
diff --git a/ktlint.py b/ktlint.py
index 72adbab..008721d 100755
--- a/ktlint.py
+++ b/ktlint.py
@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python3
 
 #
 # Copyright 2017, The Android Open Source Project