devserver: set shebangs to python2

This code isn't Python 3 compatible yet, so make sure it's pinned to 2.

BUG=chromium:998225
TEST=tests pass when python->python3

Change-Id: Ieda3edde14bd3b272fd746b5377784b07fa5b3df
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/dev-util/+/1773508
Reviewed-by: Amin Hassani <ahassani@chromium.org>
Commit-Queue: Mike Frysinger <vapier@chromium.org>
Tested-by: Mike Frysinger <vapier@chromium.org>
diff --git a/strip_package.py b/strip_package.py
old mode 100644
new mode 100755
index aee4251..60bb25a
--- a/strip_package.py
+++ b/strip_package.py
@@ -1,3 +1,5 @@
+#!/usr/bin/env python2
+# -*- coding: utf-8 -*-
 # Copyright (c) 2009-2015 The Chromium OS Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.